contest_id int32 1 2.13k | index stringclasses 62
values | problem_id stringlengths 2 6 | title stringlengths 0 67 | rating int32 0 3.5k | tags stringlengths 0 139 | statement stringlengths 0 6.96k | input_spec stringlengths 0 2.32k | output_spec stringlengths 0 1.52k | note stringlengths 0 5.06k | sample_tests stringlengths 0 1.02k | difficulty_category stringclasses 6
values | tag_count int8 0 11 | statement_length int32 0 6.96k | input_spec_length int16 0 2.32k | output_spec_length int16 0 1.52k | contest_year int16 0 21 |
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374 | C | 374C | C. Inna and Dima | 1,900 | dfs and similar; dp; graphs; implementation | Inna and Dima bought a table of size n Γ m in the shop. Each cell of the table contains a single letter: ""D"", ""I"", ""M"", ""A"".Inna loves Dima, so she wants to go through his name as many times as possible as she moves through the table. For that, Inna acts as follows: initially, Inna chooses some cell of the tabl... | The first line of the input contains two integers n and m (1 β€ n, m β€ 103). Then follow n lines that describe Inna and Dima's table. Each line contains m characters. Each character is one of the following four characters: ""D"", ""I"", ""M"", ""A"". Note that it is not guaranteed that the table contains at least one le... | If Inna cannot go through name DIMA once, print on a single line ""Poor Dima!"" without the quotes. If there is the infinite number of names DIMA Inna can go through, print ""Poor Inna!"" without the quotes. Otherwise print a single integer β the maximum number of times Inna can go through name DIMA. | Notes to the samples:In the first test sample, Inna cannot go through name DIMA a single time.In the second test sample, Inna can go through the infinite number of words DIMA. For that, she should move in the clockwise direction starting from the lower right corner.In the third test sample the best strategy is to start... | Input: 1 2DI | Output: Poor Dima! | Hard | 4 | 1,377 | 331 | 301 | 3 |
1,872 | G | 1872G | G. Replace With Product | 2,000 | brute force; greedy; math | Given an array \(a\) of \(n\) positive integers. You need to perform the following operation exactly once: Choose \(2\) integers \(l\) and \(r\) (\(1 \le l \le r \le n\)) and replace the subarray \(a[l \ldots r]\) with the single element: the product of all elements in the subarray \((a_l \cdot \ldots \cdot a_r)\).For ... | Each test consists of multiple test cases. The first line contains a single integer \(t\) (\(1 \le t \le 10^4\)) β the number of test cases. This is followed by the description of the test cases.The first line of each test case contains a single number \(n\) (\(1 \le n \le 2 \cdot 10^5\)) β the length of the array \(a\... | For each test case, output \(2\) integers \(l\) and \(r\) (\(1 \le l \le r \le n\)) β the boundaries of the subarray to be replaced with the product.If there are multiple solutions, output any of them. | In the first test case, after applying the operation with parameters \(l = 2, r = 4\), the array \([1, 3, 1, 3]\) turns into \([1, 9]\), with a sum equal to \(10\). It is easy to see that by replacing any other segment with a product, the sum will be less than \(10\).In the second test case, after applying the operatio... | Input: 941 3 1 341 1 2 351 1 1 1 1510 1 10 1 101122 232 1 242 1 1 362 1 2 1 1 3 | Output: 2 4 3 4 1 1 1 5 1 1 1 2 2 2 4 4 1 6 | Hard | 3 | 590 | 536 | 201 | 18 |
1,940 | B | 1940B | 0 | *special; constructive algorithms; implementation; sortings | Beginner | 4 | 0 | 0 | 0 | 19 | ||||||
1,313 | C2 | 1313C2 | C2. Skyscrapers (hard version) | 1,900 | data structures; dp; greedy | This is a harder version of the problem. In this version \(n \le 500\,000\)The outskirts of the capital are being actively built up in Berland. The company ""Kernel Panic"" manages the construction of a residential complex of skyscrapers in New Berlskva. All skyscrapers are built along the highway. It is known that the... | The first line contains a single integer \(n\) (\(1 \leq n \leq 500\,000\)) β the number of plots.The second line contains the integers \(m_1, m_2, \ldots, m_n\) (\(1 \leq m_i \leq 10^9\)) β the limit on the number of floors for every possible number of floors for a skyscraper on each plot. | Print \(n\) integers \(a_i\) β the number of floors in the plan for each skyscraper, such that all requirements are met, and the total number of floors in all skyscrapers is the maximum possible.If there are multiple answers possible, print any of them. | In the first example, you can build all skyscrapers with the highest possible height.In the second test example, you cannot give the maximum height to all skyscrapers as this violates the design code restriction. The answer \([10, 6, 6]\) is optimal. Note that the answer of \([6, 6, 8]\) also satisfies all restrictions... | Input: 51 2 3 2 1 | Output: 1 2 3 2 1 | Hard | 3 | 1,509 | 291 | 253 | 13 |
130 | G | 130G | G. CAPS LOCK ON | 1,700 | *special | You are given a string which consists of letters and other characters. Convert it to uppercase, i.e., replace all lowercase letters with corresponding uppercase ones. Keep the rest of characters unchanged. | The only line of input contains a string between 1 and 100 characters long. Each character of the string has ASCII-code between 33 (exclamation mark) and 126 (tilde), inclusive. | Output the given string, converted to uppercase. | Input: cOdEfOrCeS | Output: CODEFORCES | Medium | 1 | 205 | 177 | 48 | 1 | |
2,131 | F | 2131F | F. Unjust Binary Life | 0 | binary search; data structures; greedy; greedy; math; sortings; two pointers | Yuri is given two binary strings \(a\) and \(b\), both of which are of length \(n\). The two strings dynamically define an \(n \times n\) grid. Let \((i, j)\) denote the cell in the \(i\)-th row and \(j\)-th column. The initial value of cell \((i, j)\) has the value of \(a_i \oplus b_j\), where \(\oplus\) denotes the b... | Each test contains multiple test cases. The first line contains the number of test cases \(t\) (\(1 \le t \le 10^4\)). The description of the test cases follows. The first line of each test case contains one integer \(n\) (\(1 \le n \le 2 \cdot 10^5\)).The second line of each test case contains a binary string \(a\) (\... | For each test case, output one integer β the sum of minimum operations over all possible cells. | In the first test case, the \(2 \times 2\) grid is shown below.$$$\( 11 \\ 11 \)\(In the initial state, Yuri cannot reach any cell.Yuri can flip \)a_1\( so that the grid becomes:\)\( 00 \\ 11 \)\(and Yuri can travel to cells \)(1,1)\( and \)(1,2)\(.On the other hand, Yuri can flip \)b_1\( so that the grid becomes:\)\( ... | Input: 32110020101410101101 | Output: 5 4 24 | Beginner | 7 | 1,221 | 546 | 95 | 21 |
838 | C | 838C | C. Future Failure | 2,800 | dp; games | Alice and Bob are playing a game with a string of characters, with Alice going first. The string consists n characters, each of which is one of the first k letters of the alphabet. On a playerβs turn, they can either arbitrarily permute the characters in the words, or delete exactly one character in the word (if there ... | The first line of input will contain three integers n, k, p (1 β€ n β€ 250 000, 1 β€ k β€ 26, 108 β€ p β€ 109 + 100, p will be prime). | Print a single integer, the number of winning words for Alice, modulo p. | There are 14 strings that that Alice can win with. For example, some strings are ""bbaa"" and ""baaa"". Alice will lose on strings like ""aaaa"" or ""bbbb"". | Input: 4 2 100000007 | Output: 14 | Master | 2 | 716 | 128 | 72 | 8 |
372 | E | 372E | E. Drawing Circles is Fun | 3,000 | combinatorics; geometry | There are a set of points S on the plane. This set doesn't contain the origin O(0, 0), and for each two distinct points in the set A and B, the triangle OAB has strictly positive area.Consider a set of pairs of points (P1, P2), (P3, P4), ..., (P2k - 1, P2k). We'll call the set good if and only if: k β₯ 2. All Pi are dis... | The first line contains a single integer n (1 β€ n β€ 1000) β the number of points in S. Each of the next n lines contains four integers ai, bi, ci, di (0 β€ |ai|, |ci| β€ 50; 1 β€ bi, di β€ 50; (ai, ci) β (0, 0)). These integers represent a point .No two points coincide. | Print a single integer β the answer to the problem modulo 1000000007 (109 + 7). | Input: 10-46 46 0 360 20 -24 48-50 50 -49 49-20 50 8 40-15 30 14 284 10 -4 56 15 8 10-20 50 -3 154 34 -16 3416 34 2 17 | Output: 2 | Master | 2 | 660 | 266 | 79 | 3 | |
1,209 | E2 | 1209E2 | E2. Rotate Columns (hard version) | 2,500 | bitmasks; dp; greedy; sortings | This is a harder version of the problem. The difference is only in constraints.You are given a rectangular \(n \times m\) matrix \(a\). In one move you can choose any column and cyclically shift elements in this column. You can perform this operation as many times as you want (possibly zero). You can perform this opera... | The first line contains an integer \(t\) (\(1 \le t \le 40\)), the number of test cases in the input.The first line of each test case contains integers \(n\) and \(m\) (\(1 \le n \le 12\), \(1 \le m \le 2000\)) β the number of rows and the number of columns in the given matrix \(a\). Each of the following \(n\) lines c... | Print \(t\) integers: answers for all test cases in the order they are given in the input. | In the first test case you can shift the third column down by one, this way there will be \(r_1 = 5\) and \(r_2 = 7\).In the second case you can don't rotate anything at all, this way there will be \(r_1 = r_2 = 10\) and \(r_3 = 9\). | Input: 3 2 3 2 5 7 4 2 4 3 6 4 1 5 2 10 4 8 6 6 4 9 10 5 4 9 5 8 7 3 3 9 9 9 1 1 1 1 1 1 | Output: 12 29 27 | Expert | 4 | 556 | 396 | 90 | 12 |
262 | A | 262A | A. Roma and Lucky Numbers | 800 | implementation | Roma (a popular Russian name that means 'Roman') loves the Little Lvov Elephant's lucky numbers.Let us remind you that lucky numbers are positive integers whose decimal representation only contains lucky digits 4 and 7. For example, numbers 47, 744, 4 are lucky and 5, 17, 467 are not.Roma's got n positive integers. He ... | The first line contains two integers n, k (1 β€ n, k β€ 100). The second line contains n integers ai (1 β€ ai β€ 109) β the numbers that Roma has. The numbers in the lines are separated by single spaces. | In a single line print a single integer β the answer to the problem. | In the first sample all numbers contain at most four lucky digits, so the answer is 3.In the second sample number 447 doesn't fit in, as it contains more than two lucky digits. All other numbers are fine, so the answer is 2. | Input: 3 41 2 4 | Output: 3 | Beginner | 1 | 443 | 199 | 68 | 2 |
1,702 | C | 1702C | C. Train and Queries | 1,100 | data structures; greedy | Along the railroad there are stations indexed from \(1\) to \(10^9\). An express train always travels along a route consisting of \(n\) stations with indices \(u_1, u_2, \dots, u_n\), where (\(1 \le u_i \le 10^9\)). The train travels along the route from left to right. It starts at station \(u_1\), then stops at statio... | The first line of the input contains an integer \(t\) (\(1 \le t \le 10^4\)) βthe number of test cases in the test.The descriptions of the test cases follow.The first line of each test case is empty.The second line of each test case contains two integers: \(n\) and \(k\) (\(1 \le n \le 2 \cdot 10^5, 1 \le k \le 2 \cdot... | For each test case, output on a separate line: YES, if you can travel by train from the station with index \(a_j\) to the station with index \(b_j\) NO otherwise. You can output YES and NO in any case (for example, strings yEs, yes, Yes and YES will be recognized as a positive response). | The first test case is explained in the problem statement. | Input: 36 33 7 1 5 1 43 51 73 103 31 2 12 11 24 57 52 1 1 1 2 4 41 31 42 14 11 2 | Output: YES NO NO YES YES NO NO YES YES NO YES | Easy | 2 | 1,415 | 972 | 288 | 17 |
2,087 | A | 2087A | A. Password Generator | 0 | *special | Monocarp is going to register on the Codeforces website, but he can't come up with a sufficiently secure password. The requirements that his password must meet are as follows: the password must consist of digits, as well as uppercase and lowercase letters of the Latin alphabet; there must be exactly \(a\) digits, exact... | The first line contains a single integer \(t\) (\(1 \le t \le 1000\)) β the number of test cases.Each test case consists of one line containing three integers \(a\), \(b\), and \(c\) (\(1 \le a, b, c \le 10\)). | For each test case, output one line containing any suitable password. It can be shown that there is always at least one password that meets the requirements. | Input: 22 1 63 3 6 | Output: abaCaba42 b3sTpAs5w0rD | Beginner | 1 | 629 | 210 | 157 | 20 | |
362 | E | 362E | E. Petya and Pipes | 2,300 | flows; graphs; shortest paths | A little boy Petya dreams of growing up and becoming the Head Berland Plumber. He is thinking of the problems he will have to solve in the future. Unfortunately, Petya is too inexperienced, so you are about to solve one of such problems for Petya, the one he's the most interested in.The Berland capital has n water tank... | The first line contains two space-separated integers n and k (2 β€ n β€ 50, 0 β€ k β€ 1000). Then follow n lines, each line contains n integers separated by single spaces. The i + 1-th row and j-th column contain number cij β the width of the pipe that goes from tank i to tank j (0 β€ cij β€ 106, cii = 0). If cij = 0, then t... | Print a single integer β the maximum amount of water that can be transmitted from the main tank to the sewer tank per a unit of time. | In the first test Petya can increase width of the pipe that goes from the 1st to the 2nd water tank by 7 units.In the second test Petya can increase width of the pipe that goes from the 1st to the 2nd water tank by 4 units, from the 2nd to the 3rd water tank by 3 units, from the 3rd to the 4th water tank by 2 units and... | Input: 5 70 1 0 2 00 0 4 10 00 0 0 0 50 0 0 0 100 0 0 0 0 | Output: 10 | Expert | 3 | 1,099 | 358 | 133 | 3 |
457 | A | 457A | A. Golden System | 1,700 | math; meet-in-the-middle | Piegirl got bored with binary, decimal and other integer based counting systems. Recently she discovered some interesting properties about number , in particular that q2 = q + 1, and she thinks it would make a good base for her new unique system. She called it ""golden system"". In golden system the number is a non-emp... | Input consists of two lines β one for each number. Each line contains non-empty string consisting of '0' and '1' characters. The length of each string does not exceed 100000. | Print "">"" if the first number is larger, ""<"" if it is smaller and ""="" if they are equal. | In the first example first number equals to , while second number is approximately 1.6180339882 + 1.618033988 + 1 β 5.236, which is clearly a bigger number.In the second example numbers are equal. Each of them is β 2.618. | Input: 1000111 | Output: < | Medium | 2 | 762 | 174 | 94 | 4 |
101 | C | 101C | C. Vectors | 2,000 | implementation; math | At a geometry lesson Gerald was given a task: to get vector B out of vector A. Besides, the teacher permitted him to perform the following operations with vector Π: Turn the vector by 90 degrees clockwise. Add to the vector a certain vector C.Operations could be performed in any order any number of times.Can Gerald cop... | The first line contains integers x1 ΠΈ y1 β the coordinates of the vector A ( - 108 β€ x1, y1 β€ 108). The second and the third line contain in the similar manner vectors B and C (their coordinates are integers; their absolute value does not exceed 108). | Print ""YES"" (without the quotes) if it is possible to get vector B using the given operations. Otherwise print ""NO"" (without the quotes). | Input: 0 01 10 1 | Output: YES | Hard | 2 | 336 | 251 | 141 | 1 | |
926 | J | 926J | J. Segments | 2,100 | data structures | There is a straight line colored in white. n black segments are added on it one by one.After each segment is added, determine the number of connected components of black segments (i. e. the number of black segments in the union of the black segments). In particular, if one segment ends in a point x, and another segment... | The first line contains a single integer n (1 β€ n β€ 200 000) β the number of segments.The i-th of the next n lines contains two integers li and ri (1 β€ li < ri β€ 109) β the coordinates of the left and the right ends of the i-th segment. The segments are listed in the order they are added on the white line. | Print n integers β the number of connected components of black segments after each segment is added. | In the first example there are two components after the addition of the first two segments, because these segments do not intersect. The third added segment intersects the left segment and touches the right segment at the point 4 (these segments belong to the same component, according to the statements). Thus the numbe... | Input: 31 34 52 4 | Output: 1 2 1 | Hard | 1 | 402 | 307 | 100 | 9 |
816 | A | 816A | A. Karen and Morning | 1,000 | brute force; implementation | Karen is getting ready for a new school day! It is currently hh:mm, given in a 24-hour format. As you know, Karen loves palindromes, and she believes that it is good luck to wake up when the time is a palindrome.What is the minimum number of minutes she should sleep, such that, when she wakes up, the time is a palindro... | The first and only line of input contains a single string in the format hh:mm (00 β€ hh β€ 23, 00 β€ mm β€ 59). | Output a single integer on a line by itself, the minimum number of minutes she should sleep, such that, when she wakes up, the time is a palindrome. | In the first test case, the minimum number of minutes Karen should sleep for is 11. She can wake up at 05:50, when the time is a palindrome.In the second test case, Karen can wake up immediately, as the current time, 13:31, is already a palindrome.In the third test case, the minimum number of minutes Karen should sleep... | Input: 05:39 | Output: 11 | Beginner | 2 | 556 | 107 | 148 | 8 |
2,119 | E | 2119E | E. And Constraint | 2,600 | bitmasks; dp; greedy | wowaka & Hatsune Miku - Tosenbo You are given a sequence \(a\) of length \(n-1\) and a sequence \(b\) of length \(n\). You can perform the following operation any number of times (possibly zero): choose an index \(1 \le i \le n\) and increment \(b_i\) by \(1\) (i.e., set \(b_i \leftarrow b_i + 1\)). Your goal is to per... | Each test contains multiple test cases. The first line contains the number of test cases \(t\) (\(1 \le t \le 10^4\)). The description of the test cases follows. The first line contains a single integer \(n\) (\(2 \le n \le 10^5\)).The second line contains \(n-1\) integers \(a_1, a_2, \ldots, a_{n-1}\) (\(0 \le a_i < 2... | For each test case, you need to output only one integer.If the goal can be achieved, output one integer β the minimum number of operations required. Otherwise, output \(-1\). | In the first test case, one of the optimal strategies is to use \(4\) operations to make \(b = [1,5,4,4]\), which satisfies all the conditions. We can prove that it is impossible to use fewer than \(4\) operations.In the second test case, since \(b_1 \, \& \, b_2 = 4\) and \(b_2 \, \& \, b_3 =0\), then \(b_3 \, \& \, 4... | Input: 741 4 41 2 3 444 0 41 1 1 1210 031 10 1 261 2 3 4 51 1 4 5 1 4200 040 1 0536870911 536870911 536870911 536870911 | Output: 4 -1 2 2 -1 0 536870916 | Expert | 3 | 563 | 510 | 174 | 21 |
33 | D | 33D | D. Knights | 2,000 | geometry; graphs; shortest paths; sortings | Berland is facing dark times again. The army of evil lord Van de Mart is going to conquer the whole kingdom. To the council of war called by the Berland's king Valery the Severe came n knights. After long discussions it became clear that the kingdom has exactly n control points (if the enemy conquers at least one of th... | The first input line contains three integers n, m, k (1 β€ n, m β€ 1000, 0 β€ k β€ 100000). Then follow n lines, each containing two integers Kxi, Kyi ( - 109 β€ Kxi, Kyi β€ 109) β coordinates of control point with index i. Control points can coincide.Each of the following m lines describes fence with index i with three inte... | Output exactly k lines, each containing one integer β the answer to the corresponding request. | Input: 2 1 10 03 32 0 01 2 | Output: 1 | Hard | 4 | 1,035 | 593 | 94 | 0 | |
2,056 | E | 2056E | E. Nested Segments | 2,500 | combinatorics; dfs and similar; dp; dsu; math | A set \(A\) consisting of pairwise distinct segments \([l, r]\) with integer endpoints is called good if \(1\le l\le r\le n\), and for any pair of distinct segments \([l_i, r_i], [l_j, r_j]\) in \(A\), exactly one of the following conditions holds: \(r_i < l_j\) or \(r_j < l_i\) (the segments do not intersect) \(l_i \l... | Each test contains multiple test cases. The first line contains the number of test cases \(t\) (\(1 \le t \le 10^4\)). The description of the test cases follows. The first line of each test case contains two integers \(n\) and \(m\) (\(1 \le n \le 2 \cdot 10^5\), \(0 \le m \le 2 \cdot 10^5\)) β the maximum right endpoi... | For each test case, output a single integer representing the number of different ways, modulo \(998\,244\,353\), that you can add the maximum number of additional segments to set \(S\) while ensuring that set \(S\) remains good. | In the first example, the only possible segment is \([1, 1]\), so \(T = \{[1, 1]\}\) has the maximum size, and it is the only solution.In the second example, it is not possible to add any additional segments to set \(S\). Hence, the only way to add segments to \(S\) is adding nothing.In the third example, it is possibl... | Input: 61 02 31 12 21 25 21 32 34 11 16 21 34 62300 0 | Output: 1 1 2 5 4 187997613 | Expert | 5 | 1,198 | 736 | 228 | 20 |
1,925 | A | 1925A | A. We Got Everything Covered! | 800 | constructive algorithms; greedy; strings | You are given two positive integers \(n\) and \(k\). Your task is to find a string \(s\) such that all possible strings of length \(n\) that can be formed using the first \(k\) lowercase English alphabets occur as a subsequence of \(s\). If there are multiple answers, print the one with the smallest length. If there ar... | The first line of input contains a single integer \(t\) (\(1\leq t\leq 676\)) denoting the number of test cases.Each test case consists of a single line of input containing two integers \(n\) (\(1\leq n\leq 26\)) and \(k\) (\(1\leq k\leq 26\)). | For each test case, print a single line containing a single string \(s\) which satisfies the above property. If there are multiple answers, print the one with the smallest length. If there are still multiple answers, you may print any of them. | For the first test case, there are two strings of length \(1\) which can be formed using the first \(2\) lowercase English alphabets, and they are present in \(s\) as a subsequence as follows: \(\texttt{a}: {\color{red}{\texttt{a}}}\texttt{b}\) \(\texttt{b}: \texttt{a}{\color{red}{\texttt{b}}}\) For the second test cas... | Input: 41 22 12 22 3 | Output: ab aa baab abcbac | Beginner | 3 | 576 | 244 | 243 | 19 |
29 | D | 29D | D. Ant on the Tree | 2,000 | constructive algorithms; dfs and similar; trees | Connected undirected graph without cycles is called a tree. Trees is a class of graphs which is interesting not only for people, but for ants too.An ant stands at the root of some tree. He sees that there are n vertexes in the tree, and they are connected by n - 1 edges so that there is a path between any pair of verte... | The first line contains integer n (3 β€ n β€ 300) β amount of vertexes in the tree. Next n - 1 lines describe edges. Each edge is described with two integers β indexes of vertexes which it connects. Each edge can be passed in any direction. Vertexes are numbered starting from 1. The root of the tree has number 1. The las... | If the required route doesn't exist, output -1. Otherwise, output 2n - 1 numbers, describing the route. Every time the ant comes to a vertex, output it's index. | Input: 31 22 33 | Output: 1 2 3 2 1 | Hard | 3 | 621 | 528 | 160 | 0 | |
1,034 | B | 1034B | B. Little C Loves 3 II | 2,200 | brute force; constructive algorithms; flows; graph matchings | Little C loves number Β«3Β» very much. He loves all things about it.Now he is playing a game on a chessboard of size \(n \times m\). The cell in the \(x\)-th row and in the \(y\)-th column is called \((x,y)\). Initially, The chessboard is empty. Each time, he places two chessmen on two different empty cells, the Manhatta... | A single line contains two integers \(n\) and \(m\) (\(1 \leq n,m \leq 10^9\)) β the number of rows and the number of columns of the chessboard. | Print one integer β the maximum number of chessmen Little C can place. | In the first example, the Manhattan distance between any two cells is smaller than \(3\), so the answer is \(0\).In the second example, a possible solution is \((1,1)(3,2)\), \((1,2)(3,3)\), \((2,1)(1,3)\), \((3,1)(2,3)\). | Input: 2 2 | Output: 0 | Hard | 4 | 604 | 144 | 70 | 10 |
1,415 | A | 1415A | A. Prison Break | 800 | brute force; math | There is a prison that can be represented as a rectangular matrix with \(n\) rows and \(m\) columns. Therefore, there are \(n \cdot m\) prison cells. There are also \(n \cdot m\) prisoners, one in each prison cell. Let's denote the cell in the \(i\)-th row and the \(j\)-th column as \((i, j)\).There's a secret tunnel i... | The first line contains an integer \(t\) \((1 \le t \le 10^4)\), the number of test cases.Each of the next \(t\) lines contains four space-separated integers \(n\), \(m\), \(r\), \(c\) (\(1 \le r \le n \le 10^9\), \(1 \le c \le m \le 10^9\)). | Print \(t\) lines, the answers for each test case. | Input: 3 10 10 1 1 3 5 2 4 10 2 5 1 | Output: 18 4 6 | Beginner | 2 | 1,051 | 242 | 50 | 14 | |
1,954 | E | 1954E | E. Chain Reaction | 2,200 | binary search; data structures; dsu; greedy; implementation; math; number theory | There are \(n\) monsters standing in a row. The \(i\)-th monster has \(a_i\) health points.Every second, you can choose one alive monster and launch a chain lightning at it. The lightning deals \(k\) damage to it, and also spreads to the left (towards decreasing \(i\)) and to the right (towards increasing \(i\)) to ali... | The first line contains a single integer \(n\) (\(1 \le n \le 10^5\)) β the number of monsters.The second line contains \(n\) integers \(a_1, a_2, \dots, a_n\) (\(1 \le a_i \le 10^5\)) β the health points of the \(i\)-th monster. | For each \(k\) from \(1\) to \(\max(a_1, a_2, \dots, a_n)\), output the minimum number of seconds it takes to kill all the monsters. | Input: 35 2 7 | Output: 10 6 4 3 2 2 1 | Hard | 7 | 1,212 | 229 | 132 | 19 | |
978 | D | 978D | D. Almost Arithmetic Progression | 1,500 | brute force; implementation; math | Polycarp likes arithmetic progressions. A sequence \([a_1, a_2, \dots, a_n]\) is called an arithmetic progression if for each \(i\) (\(1 \le i < n\)) the value \(a_{i+1} - a_i\) is the same. For example, the sequences \([42]\), \([5, 5, 5]\), \([2, 11, 20, 29]\) and \([3, 2, 1, 0]\) are arithmetic progressions, but \([... | The first line contains a single integer \(n\) \((1 \le n \le 100\,000)\) β the number of elements in \(b\).The second line contains a sequence \(b_1, b_2, \dots, b_n\) \((1 \le b_i \le 10^{9})\). | If it is impossible to make an arithmetic progression with described operations, print -1. In the other case, print non-negative integer β the minimum number of elements to change to make the given sequence becomes an arithmetic progression. The only allowed operation is to add/to subtract one from an element (can't us... | In the first example Polycarp should increase the first number on \(1\), decrease the second number on \(1\), increase the third number on \(1\), and the fourth number should left unchanged. So, after Polycarp changed three elements by one, his sequence became equals to \([25, 20, 15, 10]\), which is an arithmetic prog... | Input: 424 21 14 10 | Output: 3 | Medium | 3 | 1,040 | 196 | 360 | 9 |
117 | E | 117E | E. Tree or not Tree | 2,900 | data structures; divide and conquer; graphs; implementation; trees | You are given an undirected connected graph G consisting of n vertexes and n edges. G contains no self-loops or multiple edges. Let each edge has two states: on and off. Initially all edges are switched off.You are also given m queries represented as (v, u) β change the state of all edges on the shortest path from vert... | The first line contains two integers n and m (3 β€ n β€ 105, 1 β€ m β€ 105). Then n lines describe the graph edges as a b (1 β€ a, b β€ n). Next m lines contain the queries as v u (1 β€ v, u β€ n). It is guaranteed that the graph is connected, does not have any self-loops or multiple edges. | Print m lines, each containing one integer β the query results. | Let's consider the first sample. We'll highlight the switched on edges blue on the image. The graph before applying any operations. No graph edges are switched on, that's why there initially are 5 connected components. The graph after query v = 5, u = 4. We can see that the graph has three components if we only conside... | Input: 5 22 14 32 42 54 15 41 5 | Output: 33 | Master | 5 | 803 | 283 | 63 | 1 |
1,466 | D | 1466D | D. 13th Labour of Heracles | 1,500 | data structures; greedy; sortings; trees | You've probably heard about the twelve labors of Heracles, but do you have any idea about the thirteenth? It is commonly assumed it took him a dozen years to complete the twelve feats, so on average, a year to accomplish every one of them. As time flows faster these days, you have minutes rather than months to solve th... | In the first line of input, there is a single integer \(t\) (\(1 \leq t \leq 10^5\)) denoting the number of test cases. Then \(t\) test cases follow. First line of each test case contains a single integer \(n\) (\(2 \leq n \leq 10^5\)). The second line consists of \(n\) integers \(w_1, w_2, \dots, w_n\) (\(0 \leq w_i \... | For every test case, your program should print one line containing \(n - 1\) integers separated with a single space. The \(i\)-th number in a line should be the maximal value of a \(i\)-coloring of the tree. | The optimal \(k\)-colorings from the first test case are the following: In the \(1\)-coloring all edges are given the same color. The subgraph of color \(1\) contains all the edges and vertices from the original graph. Hence, its value equals \(3 + 5 + 4 + 6 = 18\). In an optimal \(2\)-coloring edges \((2, 1)\) and \((... | Input: 4 4 3 5 4 6 2 1 3 1 4 3 2 21 32 2 1 6 20 13 17 13 13 11 2 1 3 1 4 1 5 1 6 1 4 10 6 6 6 1 2 2 3 4 1 | Output: 18 22 25 53 87 107 127 147 167 28 38 44 | Medium | 4 | 1,322 | 649 | 207 | 14 |
1,670 | B | 1670B | B. Dorms War | 1,100 | brute force; implementation; strings | Hosssam decided to sneak into Hemose's room while he is sleeping and change his laptop's password. He already knows the password, which is a string \(s\) of length \(n\). He also knows that there are \(k\) special letters of the alphabet: \(c_1,c_2,\ldots, c_k\).Hosssam made a program that can do the following. The pro... | The first line contains a single integer \(t\) (\(1 \le t \le 10^5\)) β the number of test cases. Then \(t\) test cases follow.The first line of each test case contains a single integer \(n\) (\(2 \le n \le 10^5\)) β the initial length of the password.The next line contains a string \(s\) consisting of \(n\) lowercase ... | For each test case, print the maximum number of times Hosssam can run the program without displaying the error message, on a new line. | In the first test case, the program can run \(5\) times as follows: \(\text{iloveslim} \to \text{ilovslim} \to \text{iloslim} \to \text{ilslim} \to \text{islim} \to \text{slim}\)In the second test case, the program can run \(2\) times as follows: \(\text{joobeel} \to \text{oel} \to \text{el}\)In the third test case, th... | Input: 109iloveslim1 s7joobeel2 o e7basiozi2 s i6khater1 r7abobeih6 a b e h i o5zondl5 a b c e f6shoman2 a h7shetwey2 h y5samez1 m6mouraz1 m | Output: 5 2 3 5 1 0 3 5 2 0 | Easy | 3 | 1,241 | 602 | 134 | 16 |
732 | E | 732E | E. Sockets | 2,100 | greedy; sortings | The ICM ACPC World Finals is coming! Unfortunately, the organizers of the competition were so busy preparing tasks that totally missed an important technical point β the organization of electricity supplement for all the participants workstations.There are n computers for participants, the i-th of which has power equal... | The first line contains two integers n and m (1 β€ n, m β€ 200 000) β the number of computers and the number of sockets.The second line contains n integers p1, p2, ..., pn (1 β€ pi β€ 109) β the powers of the computers. The third line contains m integers s1, s2, ..., sm (1 β€ si β€ 109) β the power of the sockets. | In the first line print two numbers c and u β the maximum number of computers which can at the same time be connected to electricity and the minimum number of adapters needed to connect c computers.In the second line print m integers a1, a2, ..., am (0 β€ ai β€ 109), where ai equals the number of adapters orginizers need... | Input: 2 21 12 2 | Output: 2 21 11 2 | Hard | 2 | 1,971 | 309 | 880 | 7 | |
1,952 | B | 1952B | B. Is it stated? | 0 | *special; strings | The first line contains an integer \(t\) (\(1 \leq t \leq 100\)) β the number of testcases.The following \(t\) lines each contain a string of length at most \(100\) consisting of lowercase English letters. | For each test case, output ""YES"" or ""NO"", denoting the answer. | Input: 10isitstatedsubmitacacceptedwawronganswertletimelimitexceeded | Output: NO YES NO YES NO NO NO NO NO YES | Beginner | 2 | 0 | 205 | 66 | 19 | ||
708 | B | 708B | B. Recover the String | 1,900 | constructive algorithms; greedy; implementation; math | For each string s consisting of characters '0' and '1' one can define four integers a00, a01, a10 and a11, where axy is the number of subsequences of length 2 of the string s equal to the sequence {x, y}. In these problem you are given four integers a00, a01, a10, a11 and have to find any non-empty string s that matche... | The only line of the input contains four non-negative integers a00, a01, a10 and a11. Each of them doesn't exceed 109. | If there exists a non-empty string that matches four integers from the input, print it in the only line of the output. Otherwise, print ""Impossible"". The length of your answer must not exceed 1 000 000. | Input: 1 2 3 4 | Output: Impossible | Hard | 4 | 477 | 118 | 204 | 7 | |
1,037 | H | 1037H | H. Security | 3,200 | data structures; string suffix structures | Some programming website is establishing a secure communication protocol. For security reasons, they want to choose several more or less random strings.Initially, they have a string \(s\) consisting of lowercase English letters. Now they want to choose \(q\) strings using the following steps, and you are to help them. ... | The first line of input contains a non-empty string \(s\) (\(1 \leq |s| \leq 10^{5}\)) consisting of lowercase English letters.The second line contains an integer \(q\) (\(1 \le q \le 2 \cdot 10^5\)) β the number of strings to select.Each of the next \(q\) lines contains two integers \(l\), \(r\) (\(1 \leq l \leq r \le... | Output \(q\) lines, each of them should contain the desired string or \(-1\), if there is no such string. | Consider the first example.The string \(s\) is ""baa"". The queries are as follows. We consider the substring \(s_1 s_2\) that is ""ba"". It has substrings ""b"", ""a"" and ""ba"", since none of them is greater than the query string ""ba"", the answer is \(-1\). We consider substring ""aa"". Among its substrings only "... | Input: baa51 2 ba2 3 a1 2 b2 3 aa1 3 b | Output: -1aaba-1ba | Master | 2 | 1,124 | 484 | 105 | 10 |
177 | B1 | 177B1 | B1. Rectangular Game | 1,000 | number theory | The Smart Beaver from ABBYY decided to have a day off. But doing nothing the whole day turned out to be too boring, and he decided to play a game with pebbles. Initially, the Beaver has n pebbles. He arranges them in a equal rows, each row has b pebbles (a > 1). Note that the Beaver must use all the pebbles he has, i. ... | The single line of the input contains a single integer n β the initial number of pebbles the Smart Beaver has.The input limitations for getting 30 points are: 2 β€ n β€ 50 The input limitations for getting 100 points are: 2 β€ n β€ 109 | Print a single number β the maximum possible result of the game. | Consider the first example (c1 = 10). The possible options for the game development are: Arrange the pebbles in 10 rows, one pebble per row. Then c2 = 1, and the game ends after the first move with the result of 11. Arrange the pebbles in 5 rows, two pebbles per row. Then c2 = 2, and the game continues. During the seco... | Input: 10 | Output: 16 | Beginner | 1 | 1,143 | 231 | 64 | 1 |
74 | D | 74D | D. Hanger | 2,400 | data structures | In one very large and very respectable company there is a cloakroom with a coat hanger. It is represented by n hooks, positioned in a row. The hooks are numbered with positive integers from 1 to n from the left to the right.The company workers have a very complicated work schedule. At the beginning of a work day all th... | The first line contains two integers n, q (1 β€ n β€ 109, 1 β€ q β€ 105), which are the number of hooks on the hanger and the number of requests correspondingly. Then follow q lines with requests, sorted according to time. The request of the type ""0 i j"" (1 β€ i β€ j β€ n) β is the director's request. The input data has at ... | For each director's request in the input data print a single number on a single line β the number of coats hanging on the hooks from the i-th one to the j-th one inclusive. | Input: 9 11120 5 81130 3 890 6 960 1 9 | Output: 2325 | Expert | 1 | 1,621 | 688 | 172 | 0 | |
1,312 | B | 1312B | B. Bogosort | 1,000 | constructive algorithms; sortings | You are given an array \(a_1, a_2, \dots , a_n\). Array is good if for each pair of indexes \(i < j\) the condition \(j - a_j \ne i - a_i\) holds. Can you shuffle this array so that it becomes good? To shuffle an array means to reorder its elements arbitrarily (leaving the initial order is also an option).For example, ... | The first line contains one integer \(t\) (\(1 \le t \le 100\)) β the number of test cases.The first line of each test case contains one integer \(n\) (\(1 \le n \le 100\)) β the length of array \(a\).The second line of each test case contains \(n\) integers \(a_1, a_2, \dots , a_n\) (\(1 \le a_i \le 100\)). | For each test case print the shuffled version of the array \(a\) which is good. | Input: 3 1 7 4 1 1 3 5 6 3 2 1 5 6 4 | Output: 7 1 5 1 3 2 4 6 1 3 5 | Beginner | 2 | 600 | 309 | 79 | 13 | |
893 | B | 893B | B. Beautiful Divisors | 1,000 | brute force; implementation | Recently Luba learned about a special kind of numbers that she calls beautiful numbers. The number is called beautiful iff its binary representation consists of k + 1 consecutive ones, and then k consecutive zeroes.Some examples of beautiful numbers: 12 (110); 1102 (610); 11110002 (12010); 1111100002 (49610). More form... | The only line of input contains one number n (1 β€ n β€ 105) β the number Luba has got. | Output one number β the greatest beautiful divisor of Luba's number. It is obvious that the answer always exists. | Input: 3 | Output: 1 | Beginner | 2 | 552 | 85 | 113 | 8 | |
745 | B | 745B | B. Hongcow Solves A Puzzle | 1,400 | implementation | Hongcow likes solving puzzles.One day, Hongcow finds two identical puzzle pieces, with the instructions ""make a rectangle"" next to them. The pieces can be described by an n by m grid of characters, where the character 'X' denotes a part of the puzzle and '.' denotes an empty part of the grid. It is guaranteed that th... | The first line of input will contain two integers n and m (1 β€ n, m β€ 500), the dimensions of the puzzle piece.The next n lines will describe the jigsaw piece. Each line will have length m and will consist of characters '.' and 'X' only. 'X' corresponds to a part of the puzzle piece, '.' is an empty space.It is guarant... | Output ""YES"" if it is possible for Hongcow to make a rectangle. Output ""NO"" otherwise. | For the first sample, one example of a rectangle we can form is as follows 111222111222For the second sample, it is impossible to put two of those pieces without rotating or flipping to form a rectangle.In the third sample, we can shift the first tile by one to the right, and then compose the following rectangle: ........ | Input: 2 3XXXXXX | Output: YES | Easy | 1 | 1,044 | 427 | 90 | 7 |
1,688 | C | 1688C | C. Manipulating History | 1,700 | constructive algorithms; greedy; strings | As a human, she can erase history of its entirety. As a Bai Ze (Hakutaku), she can create history out of nothingness.βPerfect Memento in Strict SenseKeine has the ability to manipulate history. The history of Gensokyo is a string \(s\) of length \(1\) initially. To fix the chaos caused by Yukari, she needs to do the fo... | Each test contains multiple test cases. The first line contains a single integer \(T\) (\(1 \leq T \leq 10^3\)) β the number of test cases. The description of the test cases follows.The first line of each test case contains a single integer \(n\) (\(1 \le n < 10 ^ 5\)) β the number of operations.The next \(2n\) lines c... | For each test case, print the initial string in one line. | Test case 1:Initially \(s\) is ""a"". In the first operation, Keine chooses ""a"", and replaces it with ""ab"". \(s\) becomes ""ab"". In the second operation, Keine chooses ""b"", and replaces it with ""cd"". \(s\) becomes ""acd"".So the final string is ""acd"", and \(t=[\)""a"", ""ab"", ""b"", ""cd""\(]\) before being... | Input: 22aabbcdacd3zaaaayakumoranyakumoran | Output: a z | Medium | 3 | 1,382 | 782 | 57 | 16 |
533 | D | 533D | D. Landmarks | 3,000 | data structures; dp | We have an old building with n + 2 columns in a row. These columns support the ceiling. These columns are located in points with coordinates 0 = x0 < x1 < ... < xn < xn + 1. The leftmost and the rightmost columns are special, we will call them bearing, the other columns are ordinary. For each column we know its durabil... | The first line contains integer n (1 β€ n β€ 105) β the number of ordinary columns.The second line contains n + 2 integers x0, x1, ..., xn, xn + 1 (x0 = 0, xi < xi + 1 for 0 β€ i β€ n, xn + 1 β€ 109) β the coordinates of the columns.The third line contains n integers d1, d2, ..., dn (1 β€ di β€ 109). | Print a single number β the minimum possible durability of the column that you need to add in order to make the building stay. If you do not have to add the column, please print 0. Your answer will be checked with the relative or absolute error 10 - 4. | Input: 20 20 40 10015 40 | Output: 10 | Master | 2 | 1,772 | 294 | 252 | 5 | |
36 | B | 36B | B. Fractal | 1,600 | implementation | Ever since Kalevitch, a famous Berland abstractionist, heard of fractals, he made them the main topic of his canvases. Every morning the artist takes a piece of graph paper and starts with making a model of his future canvas. He takes a square as big as n Γ n squares and paints some of them black. Then he takes a clean... | The first line contains integers n and k (2 β€ n β€ 3, 1 β€ k β€ 5), where k is the amount of steps of the algorithm. Each of the following n lines contains n symbols that determine the model. Symbol Β«.Β» stands for a white square, whereas Β«*Β» stands for a black one. It is guaranteed that the model has at least one white sq... | Output a matrix nk Γ nk which is what a picture should look like after k steps of the algorithm. | Input: 2 3.*.. | Output: .*******..******.*.*****....****.***.***..**..**.*.*.*.*........ | Medium | 1 | 863 | 325 | 96 | 0 | |
1,444 | D | 1444D | D. Rectangular Polyline | 2,900 | constructive algorithms; dp; geometry | One drew a closed polyline on a plane, that consisted only of vertical and horizontal segments (parallel to the coordinate axes). The segments alternated between horizontal and vertical ones (a horizontal segment was always followed by a vertical one, and vice versa). The polyline did not contain strict self-intersecti... | The first line contains one integer \(t\) (\(1 \leq t \leq 200\)) βthe number of test cases.The first line of each test case contains one integer \(h\) (\(1 \leq h \leq 1000\)) β the number of horizontal segments. The following line contains \(h\) integers \(l_1, l_2, \dots, l_h\) (\(1 \leq l_i \leq 1000\)) β lengths o... | For each test case output Yes, if there exists at least one polyline satisfying the requirements, or No otherwise. If it does exist, in the following \(n\) lines print the coordinates of the polyline vertices, in order of the polyline traversal: the \(i\)-th line should contain two integers \(x_i\) and \(y_i\) β coordi... | In the first test case of the first example, the answer is Yes β for example, the following picture illustrates a square that satisfies the requirements: In the first test case of the second example, the desired polyline also exists. Note that, the polyline contains self-intersections, but only in the endpoints: In the... | Input: 2 2 1 1 2 1 1 2 1 2 2 3 3 | Output: Yes 1 0 1 1 0 1 0 0 No | Master | 3 | 706 | 783 | 555 | 14 |
1,970 | G3 | 1970G3 | G3. Min-Fund Prison (Hard) | 2,400 | bitmasks; dfs and similar; dp; graphs; trees | In the hard version, \(2 \leq \sum n \leq 10^5\) and \(1 \leq \sum m \leq 5 \times 10^{5}\)After a worker's strike organized by the Dementors asking for equal rights, the prison of Azkaban has suffered some damage. After settling the spirits, the Ministry of Magic is looking to renovate the prison to ensure that the De... | The first line contains one integer \(t\) (\(1 \leq t \leq 10^5\)) β the number of test cases. Then \(t\) test cases follow.The first line of each test case consists of three integers \(n, m\) and \(c\) (\(2 \leq n \leq 10^5\), \(1 \leq m \leq 5 \times 10^{5}\), \(1 \leq c \leq 10^9\))\(m\) lines follow, each consistin... | Print the \(\textbf{minimum funding}\) required to divide the prison as per the Ministry's requirements or \(-1\) if no division is possible. | In the first test case of the sample input, there is no way to divide the prison according to the Ministry's requirements.In the second test case, consider the corridor between cells \(1\) and \(5\) as the connection between the \(2\) complexes consisting of \(\{2, 3, 5, 6\}\) and \(\{1, 4\}\) cells respectively. There... | Input: 4 4 6 5 4 3 2 3 2 4 1 2 4 1 3 1 6 6 2 1 4 2 5 3 6 1 5 3 5 6 5 6 5 7 1 4 2 5 3 6 3 5 6 5 7 5 4 1 4 3 6 3 5 6 5 2 7 | Output: -1 20 25 33 | Expert | 5 | 1,828 | 719 | 141 | 19 |
754 | A | 754A | A. Lesha and array splitting | 1,200 | constructive algorithms; greedy; implementation | One spring day on his way to university Lesha found an array A. Lesha likes to split arrays into several parts. This time Lesha decided to split the array A into several, possibly one, new arrays so that the sum of elements in each of the new arrays is not zero. One more condition is that if we place the new arrays one... | The first line contains single integer n (1 β€ n β€ 100) β the number of elements in the array A.The next line contains n integers a1, a2, ..., an ( - 103 β€ ai β€ 103) β the elements of the array A. | If it is not possible to split the array A and satisfy all the constraints, print single line containing ""NO"" (without quotes).Otherwise in the first line print ""YES"" (without quotes). In the next line print single integer k β the number of new arrays. In each of the next k lines print two integers li and ri which ... | Input: 31 2 -3 | Output: YES21 23 3 | Easy | 3 | 432 | 195 | 557 | 7 | |
1,832 | E | 1832E | E. Combinatorics Problem | 2,200 | brute force; combinatorics; dp | Recall that the binomial coefficient \(\binom{x}{y}\) is calculated as follows (\(x\) and \(y\) are non-negative integers): if \(x < y\), then \(\binom{x}{y} = 0\); otherwise, \(\binom{x}{y} = \frac{x!}{y! \cdot (x-y)!}\). You are given an array \(a_1, a_2, \dots, a_n\) and an integer \(k\). You have to calculate a new... | The only line of the input contains six integers \(n\), \(a_1\), \(x\), \(y\), \(m\) and \(k\) (\(1 \le n \le 10^7\); \(0 \le a_1, x, y < m\); \(2 \le m \le 998244353\); \(1 \le k \le 5\)).The array \([a_1, a_2, \dots, a_n]\) is generated as follows: \(a_1\) is given in the input; for \(2 \le i \le n\), \(a_i = (a_{i-1... | Since outputting up to \(10^7\) integers might be too slow, you have to do the following:Let \(c_i = b_i \cdot i\) (without taking modulo \(998244353\) after the multiplication). Print the integer \(c_1 \oplus c_2 \oplus \dots \oplus c_n\), where \(\oplus\) denotes the bitwise XOR operator. | Input: 5 8 2 3 100 2 | Output: 1283 | Hard | 3 | 792 | 345 | 291 | 18 | |
1,084 | C | 1084C | C. The Fair Nut and String | 1,500 | combinatorics; dp; implementation | The Fair Nut found a string \(s\). The string consists of lowercase Latin letters. The Nut is a curious guy, so he wants to find the number of strictly increasing sequences \(p_1, p_2, \ldots, p_k\), such that: For each \(i\) (\(1 \leq i \leq k\)), \(s_{p_i} =\) 'a'. For each \(i\) (\(1 \leq i < k\)), there is such \(j... | The first line contains the string \(s\) (\(1 \leq |s| \leq 10^5\)) consisting of lowercase Latin letters. | In a single line print the answer to the problem β the number of such sequences \(p_1, p_2, \ldots, p_k\) modulo \(10^9 + 7\). | In the first example, there are \(5\) possible sequences. \([1]\), \([4]\), \([5]\), \([1, 4]\), \([1, 5]\).In the second example, there are \(4\) possible sequences. \([2]\), \([3]\), \([4]\), \([5]\).In the third example, there are \(3\) possible sequences. \([1]\), \([3]\), \([4]\). | Input: abbaa | Output: 5 | Medium | 3 | 498 | 106 | 126 | 10 |
1,095 | C | 1095C | C. Powers Of Two | 1,400 | bitmasks; greedy | A positive integer \(x\) is called a power of two if it can be represented as \(x = 2^y\), where \(y\) is a non-negative integer. So, the powers of two are \(1, 2, 4, 8, 16, \dots\).You are given two positive integers \(n\) and \(k\). Your task is to represent \(n\) as the sum of exactly \(k\) powers of two. | The only line of the input contains two integers \(n\) and \(k\) (\(1 \le n \le 10^9\), \(1 \le k \le 2 \cdot 10^5\)). | If it is impossible to represent \(n\) as the sum of \(k\) powers of two, print NO.Otherwise, print YES, and then print \(k\) positive integers \(b_1, b_2, \dots, b_k\) such that each of \(b_i\) is a power of two, and \(\sum \limits_{i = 1}^{k} b_i = n\). If there are multiple answers, you may print any of them. | Input: 9 4 | Output: YES 1 2 2 4 | Easy | 2 | 309 | 118 | 313 | 10 | |
2,095 | H | 2095H | H. Blurry Vision | 0 | *special; fft; math | Please direct your vision to line number \(x\). Now, read the word you see on that line. If you struggle, I might have to prescribe eyeglasses. | The only line contains one integer \(x\) (\(1 \leq x \leq 11\)) β the line number. | Output the word on line number \(x\). | If you fail to read the first line, even glasses won't save you. | Input: 1 | Output: CODEFORCES | Beginner | 3 | 143 | 82 | 37 | 20 |
2,064 | F | 2064F | F. We Be Summing | 2,600 | binary search; data structures; dp; two pointers | You are given an array \(a\) of length \(n\) and an integer \(k\).Call a non-empty array \(b\) of length \(m\) epic if there exists an integer \(i\) where \(1 \le i < m\) and \(\min(b_1,\ldots,b_i) + \max(b_{i + 1},\ldots,b_m) = k\).Count the number of epic subarrays\(^{\text{β}}\) of \(a\).\(^{\text{β}}\)An array \(a\... | The first line contains an integer \(t\) (\(1 \le t \le 10^4\)) β the number of testcases.The first line of each testcase contains integers \(n\) and \(k\) (\(2 \le n \le 2 \cdot 10^5\); \(n < k < 2 \cdot n\)) β the length of the array \(a\) and \(k\).The second line of each testcase contains \(n\) integers \(a_1,a_2,\... | For each testcase, output the number of epic contiguous subarrays of \(a\). | These are all the epic subarrays in the first testcase: \([2, 3, 4, 5]\), because \(\min(2, 3) + \max(4, 5) = 2 + 5 = 7\). \([3, 4]\), because \(\min(3) + \max(4) = 3 + 4 = 7\). In the second test case, every subarray that contains at least one \(6\) and at least one \(7\) is epic. | Input: 65 71 2 3 4 57 136 6 6 6 7 7 76 94 5 6 6 5 15 95 5 4 5 55 63 3 3 3 36 84 5 4 5 4 5 | Output: 2 12 3 8 10 4 | Expert | 4 | 527 | 425 | 75 | 20 |
1,433 | A | 1433A | A. Boring Apartments | 800 | implementation; math | There is a building consisting of \(10~000\) apartments numbered from \(1\) to \(10~000\), inclusive.Call an apartment boring, if its number consists of the same digit. Examples of boring apartments are \(11, 2, 777, 9999\) and so on.Our character is a troublemaker, and he calls the intercoms of all boring apartments, ... | The first line of the input contains one integer \(t\) (\(1 \le t \le 36\)) β the number of test cases.The only line of the test case contains one integer \(x\) (\(1 \le x \le 9999\)) β the apartment number of the resident who answered the call. It is guaranteed that \(x\) consists of the same digit. | For each test case, print the answer: how many digits our character pressed in total. | Input: 4 22 9999 1 777 | Output: 13 90 1 66 | Beginner | 2 | 1,095 | 301 | 85 | 14 | |
594 | D | 594D | D. REQ | 2,500 | data structures; number theory | Today on a math lesson the teacher told Vovochka that the Euler function of a positive integer Ο(n) is an arithmetic function that counts the positive integers less than or equal to n that are relatively prime to n. The number 1 is coprime to all the positive integers and Ο(1) = 1.Now the teacher gave Vovochka an array... | The first line of the input contains number n (1 β€ n β€ 200 000) β the length of the array given to Vovochka. The second line contains n integers a1, a2, ..., an (1 β€ ai β€ 106).The third line contains integer q (1 β€ q β€ 200 000) β the number of queries. Next q lines contain the queries, one per line. Each query is defin... | Print q numbers β the value of the Euler function for each query, calculated modulo 109 + 7. | In the second sample the values are calculated like that: Ο(13Β·52Β·6) = Ο(4056) = 1248 Ο(52Β·6Β·10Β·1) = Ο(3120) = 768 Ο(24Β·63Β·13Β·52Β·6Β·10Β·1) = Ο(61326720) = 12939264 Ο(63Β·13Β·52) = Ο(42588) = 11232 Ο(13Β·52Β·6Β·10) = Ο(40560) = 9984 Ο(63Β·13Β·52Β·6Β·10) = Ο(2555280) = 539136 | Input: 101 2 3 4 5 6 7 8 9 1071 13 85 64 88 107 97 10 | Output: 14608815361921441152 | Expert | 2 | 524 | 384 | 92 | 5 |
1,844 | G | 1844G | G. Tree Weights | 3,000 | bitmasks; constructive algorithms; data structures; dfs and similar; implementation; math; matrices; number theory; trees | You are given a tree with \(n\) nodes labelled \(1,2,\dots,n\). The \(i\)-th edge connects nodes \(u_i\) and \(v_i\) and has an unknown positive integer weight \(w_i\). To help you figure out these weights, you are also given the distance \(d_i\) between the nodes \(i\) and \(i+1\) for all \(1 \le i \le n-1\) (the sum ... | The first line contains a single integer \(n\) (\(2 \le n \le 10^5\)).The \(i\)-th of the next \(n-1\) lines contains two integers \(u_i\) and \(v_i\) (\(1 \le u_i,v_i \le n\), \(u_i \ne v_i\)).The last line contains \(n-1\) integers \(d_1,\dots,d_{n-1}\) (\(1 \le d_i \le 10^{12}\)).It is guaranteed that the given edge... | If there is no solution, print a single integer \(-1\). Otherwise, output \(n-1\) lines containing the weights \(w_1,\dots,w_{n-1}\).If there are multiple solutions, print any of them. | In the first sample, the tree is as follows: In the second sample, note that \(w_2\) is not allowed to be \(0\) because it must be a positive integer, so there is no solution.In the third sample, the tree is as follows: | Input: 5 1 2 1 3 2 4 2 5 31 41 59 26 | Output: 31 10 18 8 | Master | 9 | 593 | 334 | 184 | 18 |
1,401 | B | 1401B | B. Ternary Sequence | 1,100 | constructive algorithms; greedy; math | You are given two sequences \(a_1, a_2, \dots, a_n\) and \(b_1, b_2, \dots, b_n\). Each element of both sequences is either \(0\), \(1\) or \(2\). The number of elements \(0\), \(1\), \(2\) in the sequence \(a\) is \(x_1\), \(y_1\), \(z_1\) respectively, and the number of elements \(0\), \(1\), \(2\) in the sequence \(... | The first line contains one integer \(t\) (\(1 \le t \le 10^4\)) β the number of test cases.Each test case consists of two lines. The first line of each test case contains three integers \(x_1\), \(y_1\), \(z_1\) (\(0 \le x_1, y_1, z_1 \le 10^8\)) β the number of \(0\)-s, \(1\)-s and \(2\)-s in the sequence \(a\).The s... | For each test case, print the maximum possible sum of the sequence \(c\). | In the first sample, one of the optimal solutions is:\(a = \{2, 0, 1, 1, 0, 2, 1\}\)\(b = \{1, 0, 1, 0, 2, 1, 0\}\)\(c = \{2, 0, 0, 0, 0, 2, 0\}\)In the second sample, one of the optimal solutions is:\(a = \{0, 2, 0, 0, 0\}\)\(b = \{1, 1, 0, 1, 0\}\)\(c = \{0, 2, 0, 0, 0\}\)In the third sample, the only possible soluti... | Input: 3 2 3 2 3 3 1 4 0 1 2 3 0 0 0 1 0 0 1 | Output: 4 2 0 | Easy | 3 | 771 | 549 | 73 | 14 |
916 | A | 916A | A. Jamie and Alarm Snooze | 900 | brute force; implementation; math | Jamie loves sleeping. One day, he decides that he needs to wake up at exactly hh: mm. However, he hates waking up, so he wants to make waking up less painful by setting the alarm at a lucky time. He will then press the snooze button every x minutes until hh: mm is reached, and only then he will wake up. He wants to kno... | The first line contains a single integer x (1 β€ x β€ 60).The second line contains two two-digit integers, hh and mm (00 β€ hh β€ 23, 00 β€ mm β€ 59). | Print the minimum number of times he needs to press the button. | In the first sample, Jamie needs to wake up at 11:23. So, he can set his alarm at 11:17. He would press the snooze button when the alarm rings at 11:17 and at 11:20.In the second sample, Jamie can set his alarm at exactly at 01:07 which is lucky. | Input: 311 23 | Output: 2 | Beginner | 3 | 933 | 144 | 63 | 9 |
1,305 | C | 1305C | C. Kuroni and Impossible Calculation | 1,600 | brute force; combinatorics; math; number theory | To become the king of Codeforces, Kuroni has to solve the following problem.He is given \(n\) numbers \(a_1, a_2, \dots, a_n\). Help Kuroni to calculate \(\prod_{1\le i<j\le n} |a_i - a_j|\). As result can be very big, output it modulo \(m\).If you are not familiar with short notation, \(\prod_{1\le i<j\le n} |a_i - a_... | The first line contains two integers \(n\), \(m\) (\(2\le n \le 2\cdot 10^5\), \(1\le m \le 1000\)) β number of numbers and modulo.The second line contains \(n\) integers \(a_1, a_2, \dots, a_n\) (\(0 \le a_i \le 10^9\)). | Output the single number β \(\prod_{1\le i<j\le n} |a_i - a_j| \bmod m\). | In the first sample, \(|8 - 5| = 3 \equiv 3 \bmod 10\).In the second sample, \(|1 - 4|\cdot|1 - 5|\cdot|4 - 5| = 3\cdot 4 \cdot 1 = 12 \equiv 0 \bmod 12\).In the third sample, \(|1 - 4|\cdot|1 - 9|\cdot|4 - 9| = 3 \cdot 8 \cdot 5 = 120 \equiv 1 \bmod 7\). | Input: 2 10 8 5 | Output: 3 | Medium | 4 | 600 | 221 | 73 | 13 |
1,154 | F | 1154F | F. Shovels Shop | 2,100 | dp; greedy; sortings | There are \(n\) shovels in the nearby shop. The \(i\)-th shovel costs \(a_i\) bourles.Misha has to buy exactly \(k\) shovels. Each shovel can be bought no more than once.Misha can buy shovels by several purchases. During one purchase he can choose any subset of remaining (non-bought) shovels and buy this subset.There a... | The first line of the input contains three integers \(n, m\) and \(k\) (\(1 \le n, m \le 2 \cdot 10^5, 1 \le k \le min(n, 2000)\)) β the number of shovels in the shop, the number of special offers and the number of shovels Misha has to buy, correspondingly.The second line of the input contains \(n\) integers \(a_1, a_2... | Print one integer β the minimum cost of buying \(k\) shovels if Misha buys them optimally. | In the first example Misha can buy shovels on positions \(1\) and \(4\) (both with costs \(2\)) during the first purchase and get one of them for free using the first or the third special offer. And then he can buy shovels on positions \(3\) and \(6\) (with costs \(4\) and \(3\)) during the second purchase and get the ... | Input: 7 4 5 2 5 4 2 6 3 1 2 1 6 5 2 1 3 1 | Output: 7 | Hard | 3 | 894 | 691 | 90 | 11 |
1,365 | A | 1365A | A. Matrix Game | 1,100 | games; greedy; implementation | Ashish and Vivek play a game on a matrix consisting of \(n\) rows and \(m\) columns, where they take turns claiming cells. Unclaimed cells are represented by \(0\), while claimed cells are represented by \(1\). The initial state of the matrix is given. There can be some claimed cells in the initial state.In each turn, ... | The first line consists of a single integer \(t\) \((1 \le t \le 50)\) β the number of test cases. The description of the test cases follows.The first line of each test case consists of two space-separated integers \(n\), \(m\) \((1 \le n, m \le 50)\) β the number of rows and columns in the matrix.The following \(n\) l... | For each test case if Ashish wins the game print ""Ashish"" otherwise print ""Vivek"" (without quotes). | For the first case: One possible scenario could be: Ashish claims cell \((1, 1)\), Vivek then claims cell \((2, 2)\). Ashish can neither claim cell \((1, 2)\), nor cell \((2, 1)\) as cells \((1, 1)\) and \((2, 2)\) are already claimed. Thus Ashish loses. It can be shown that no matter what Ashish plays in this case, Vi... | Input: 4 2 2 0 0 0 0 2 2 0 0 0 1 2 3 1 0 1 1 1 0 3 3 1 0 0 0 0 0 1 0 0 | Output: Vivek Ashish Vivek Ashish | Easy | 3 | 805 | 447 | 103 | 13 |
1,433 | B | 1433B | B. Yet Another Bookshelf | 800 | greedy; implementation | There is a bookshelf which can fit \(n\) books. The \(i\)-th position of bookshelf is \(a_i = 1\) if there is a book on this position and \(a_i = 0\) otherwise. It is guaranteed that there is at least one book on the bookshelf.In one move, you can choose some contiguous segment \([l; r]\) consisting of books (i.e. for ... | The first line of the input contains one integer \(t\) (\(1 \le t \le 200\)) β the number of test cases. Then \(t\) test cases follow.The first line of the test case contains one integer \(n\) (\(1 \le n \le 50\)) β the number of places on a bookshelf. The second line of the test case contains \(n\) integers \(a_1, a_2... | For each test case, print one integer: the minimum number of moves required to collect all the books on the shelf as a contiguous (consecutive) segment (i.e. the segment without gaps). | In the first test case of the example, you can shift the segment \([3; 3]\) to the right and the segment \([4; 5]\) to the right. After all moves, the books form the contiguous segment \([5; 7]\). So the answer is \(2\).In the second test case of the example, you have nothing to do, all the books on the bookshelf form ... | Input: 5 7 0 0 1 0 1 0 1 3 1 0 0 5 1 1 0 0 1 6 1 0 0 0 0 1 5 1 1 0 1 1 | Output: 2 0 2 4 1 | Beginner | 2 | 1,220 | 505 | 184 | 14 |
914 | G | 914G | G. Sum the Fibonacci | 2,600 | bitmasks; divide and conquer; dp; fft; math | You are given an array s of n non-negative integers.A 5-tuple of integers (a, b, c, d, e) is said to be valid if it satisfies the following conditions: 1 β€ a, b, c, d, e β€ n (sa | sb) & sc & (sd ^ se) = 2i for some integer i sa & sb = 0 Here, '|' is the bitwise OR, '&' is the bitwise AND and '^' is the bitwise XOR oper... | The first line of input contains an integer n (1 β€ n β€ 106).The second line of input contains n integers si (0 β€ si < 217). | Output the sum as described above, modulo 109 + 7 | Input: 21 2 | Output: 32 | Expert | 5 | 553 | 123 | 49 | 9 | |
1,536 | C | 1536C | C. Diluc and Kaeya | 1,500 | data structures; dp; hashing; number theory | The tycoon of a winery empire in Mondstadt, unmatched in every possible way. A thinker in the Knights of Favonius with an exotic appearance.This time, the brothers are dealing with a strange piece of wood marked with their names. This plank of wood can be represented as a string of \(n\) characters. Each character is e... | Each test contains multiple test cases. The first line contains the number of test cases \(t\) (\(1 \le t \le 1000\)). Description of the test cases follows.The first line of each test case contains an integer \(n\) (\(1 \leq n \leq 5 \cdot 10^5\)) β the length of the wood.The second line of each test case contains a s... | For each test case, output \(n\) space separated integers. The \(i\)-th of these numbers should equal the answer for the prefix \(s_{1},s_{2},\dots,s_{i}\). | For the first test case, there is no way to partition 'D' or 'DDK' into more than one block with equal ratios of numbers of 'D' and 'K', while you can split 'DD' into 'D' and 'D'.For the second test case, you can split each prefix of length \(i\) into \(i\) blocks 'D'. | Input: 5 3 DDK 6 DDDDDD 4 DKDK 1 D 9 DKDKDDDDK | Output: 1 2 1 1 2 3 4 5 6 1 1 1 2 1 1 1 1 2 1 2 1 1 3 | Medium | 4 | 1,470 | 492 | 156 | 15 |
1,955 | C | 1955C | C. Inhabitant of the Deep Sea | 1,300 | greedy; implementation; math | \(n\) ships set out to explore the depths of the ocean. The ships are numbered from \(1\) to \(n\) and follow each other in ascending order; the \(i\)-th ship has a durability of \(a_i\).The Kraken attacked the ships \(k\) times in a specific order. First, it attacks the first of the ships, then the last, then the firs... | The first line contains an integer \(t\) (\(1 \le t \le 10^4\)) β the number of test cases.The first line of each test case contains two integers \(n\) and \(k\) (\(1 \le n \le 2 \cdot 10^5\), \(1 \le k \le 10^{15}\)) β the number of ships and how many times the Kraken will attack the ships.The second line of each test... | For each test case, output the number of ships sunk by the Kraken on a separate line. | Input: 64 51 2 4 34 61 2 4 35 202 7 1 8 22 23 22 151 52 75 2 | Output: 2 3 5 0 2 2 | Easy | 3 | 1,179 | 521 | 85 | 19 | |
491 | C | 491C | C. Deciphering | 2,300 | flows; graph matchings | One day Maria Ivanovna found a Sasha's piece of paper with a message dedicated to Olya. Maria Ivanovna wants to know what is there in a message, but unfortunately the message is ciphered. Maria Ivanovna knows that her students usually cipher their messages by replacing each letter of an original message by some another... | First line contains length of both strings N (1 β€ N β€ 2 000 000) and an integer K β number of possible answers for each of the questions (1 β€ K β€ 52). Answers to the questions are denoted as Latin letters abcde...xyzABCDE...XYZ in the order. For example for K = 6, possible answers are abcdef and for K = 30 possible ans... | In the first line output maximum possible number of correct Sasha's answers.In the second line output cipher rule as the string of length K where for each letter from the students' cipher (starting from 'a' as mentioned above) there is specified which answer does it correspond to.If there are several ways to produce ma... | Input: 10 2aaabbbaaabbbbbabbbbb | Output: 7ba | Expert | 2 | 969 | 493 | 353 | 4 | |
772 | E | 772E | E. Verifying Kingdom | 3,200 | binary search; divide and conquer; interactive; trees | This is an interactive problem.The judge has a hidden rooted full binary tree with n leaves. A full binary tree is one where every node has either 0 or 2 children. The nodes with 0 children are called the leaves of the tree. Since this is a full binary tree, there are exactly 2n - 1 nodes in the tree. The leaves of the... | The first line of input will contain a single integer n (3 β€ n β€ 1 000) β the number of leaves in the tree. | To print the final answer, print out the string ""-1"" on its own line. Then, the next line should contain 2n - 1 integers. The i-th integer should be the parent of the i-th node, or -1, if it is the root.Your answer will be judged correct if your output is isomorphic to the judge's tree. In particular, the labels of t... | For the first sample, the judge has the hidden tree:Here is a more readable format of the interaction: The last line can also be 8 6 9 8 9 7 -1 6 7. | Input: 5XZYYX | Output: 1 4 21 2 42 4 12 3 52 4 3-1-1 1 1 2 2 3 3 6 6 | Master | 4 | 1,147 | 107 | 547 | 7 |
1,481 | B | 1481B | B. New Colony | 1,100 | brute force; greedy; implementation | After reaching your destination, you want to build a new colony on the new planet. Since this planet has many mountains and the colony must be built on a flat surface you decided to flatten the mountains using boulders (you are still dreaming so this makes sense to you). You are given an array \(h_1, h_2, \dots, h_n\),... | The first line contains a single integer \(t\) (\(1 \le t \le 100\)) β the number of test cases.Each test case consists of two lines. The first line in each test case contains two integers \(n\) and \(k\) (\(1 \le n \le 100\); \(1 \le k \le 10^9\)) β the number of mountains and the number of boulders.The second line co... | For each test case, print \(-1\) if the \(k\)-th boulder will fall into the collection system. Otherwise, print the position of the \(k\)-th boulder. | Let's simulate the first case: The first boulder starts at \(i = 1\); since \(h_1 \ge h_2\) it rolls to \(i = 2\) and stops there because \(h_2 < h_3\). The new heights are \([4,2,2,3]\). The second boulder starts at \(i = 1\); since \(h_1 \ge h_2\) the boulder rolls to \(i = 2\); since \(h_2 \ge h_3\) the boulder roll... | Input: 4 4 3 4 1 2 3 2 7 1 8 4 5 4 1 2 3 3 1 5 3 1 | Output: 2 1 -1 -1 | Easy | 3 | 1,000 | 504 | 149 | 14 |
1,428 | H | 1428H | H. Rotary Laser Lock | 3,500 | binary search; interactive | This is an interactive problem.To prevent the mischievous rabbits from freely roaming around the zoo, Zookeeper has set up a special lock for the rabbit enclosure. This lock is called the Rotary Laser Lock. The lock consists of \(n\) concentric rings numbered from \(0\) to \(n-1\). The innermost ring is ring \(0\) and ... | The first line consists of 2 integers \(n\) and \(m\) \((2 \leq n \leq 100, 2 \leq m \leq 20)\), indicating the number of rings and the number of sections each ring covers. | For the first test, the configuration is the same as shown on the picture from the statement. After the first rotation (which is rotating ring \(0\) clockwise by \(1\) section), we obtain the following configuration: After the second rotation (which is rotating ring \(2\) counter-clockwise by \(1\) section), we obtain ... | Input: 3 4 4 4 3 | Output: ? 0 1 ? 2 -1 ? 1 1 ! 1 5 | Master | 2 | 2,186 | 172 | 0 | 14 | |
1,227 | A | 1227A | A. Math Problem | 1,100 | math | Your math teacher gave you the following problem:There are \(n\) segments on the \(x\)-axis, \([l_1; r_1], [l_2; r_2], \ldots, [l_n; r_n]\). The segment \([l; r]\) includes the bounds, i.e. it is a set of such \(x\) that \(l \le x \le r\). The length of the segment \([l; r]\) is equal to \(r - l\).Two segments \([a; b]... | The first line contains integer number \(t\) (\(1 \le t \le 100\)) β the number of test cases in the input. Then \(t\) test cases follow.The first line of each test case contains one integer \(n\) (\(1 \le n \le 10^{5}\)) β the number of segments. The following \(n\) lines contain segment descriptions: the \(i\)-th of ... | For each test case, output one integer β the smallest possible length of the segment which has at least one common point with all given segments. | In the first test case of the example, we can choose the segment \([5;7]\) as the answer. It is the shortest segment that has at least one common point with all given segments. | Input: 4 3 4 5 5 9 7 7 5 11 19 4 17 16 16 3 12 14 17 1 1 10 1 1 1 | Output: 2 4 0 0 | Easy | 1 | 1,003 | 483 | 145 | 12 |
1,913 | C | 1913C | C. Game with Multiset | 1,300 | binary search; bitmasks; brute force; greedy | In this problem, you are initially given an empty multiset. You have to process two types of queries: ADD \(x\) β add an element equal to \(2^{x}\) to the multiset; GET \(w\) β say whether it is possible to take the sum of some subset of the current multiset and get a value equal to \(w\). | The first line contains one integer \(m\) (\(1 \le m \le 10^5\)) β the number of queries.Then \(m\) lines follow, each of which contains two integers \(t_i\), \(v_i\), denoting the \(i\)-th query. If \(t_i = 1\), then the \(i\)-th query is ADD \(v_i\) (\(0 \le v_i \le 29\)). If \(t_i = 2\), then the \(i\)-th query is G... | For each GET query, print YES if it is possible to choose a subset with sum equal to \(w\), or NO if it is impossible. | Input: 51 01 01 02 32 4 | Output: YES NO | Easy | 4 | 290 | 356 | 118 | 19 | |
710 | F | 710F | F. String Set Queries | 2,400 | brute force; data structures; hashing; interactive; string suffix structures; strings | You should process m queries over a set D of strings. Each query is one of three kinds: Add a string s to the set D. It is guaranteed that the string s was not added before. Delete a string s from the set D. It is guaranteed that the string s is in the set D. For the given string s find the number of occurrences of the... | The first line contains integer m (1 β€ m β€ 3Β·105) β the number of queries.Each of the next m lines contains integer t (1 β€ t β€ 3) and nonempty string s β the kind of the query and the string to process. All strings consist of only lowercase English letters.The sum of lengths of all strings in the input will not exceed ... | For each query of the third kind print the only integer c β the desired number of occurrences in the string s. | Input: 51 abc3 abcabc2 abc1 aba3 abababc | Output: 22 | Expert | 6 | 735 | 326 | 110 | 7 | |
1,439 | A1 | 1439A1 | A1. Binary Table (Easy Version) | 1,500 | constructive algorithms; implementation | This is the easy version of the problem. The difference between the versions is in the number of possible operations that can be made. You can make hacks if and only if you solved both versions of the problem.You are given a binary table of size \(n \times m\). This table consists of symbols \(0\) and \(1\).You can mak... | The first line contains a single integer \(t\) (\(1 \leq t \leq 5000\)) β the number of test cases. The next lines contain descriptions of test cases.The first line of the description of each test case contains two integers \(n\), \(m\) (\(2 \leq n, m \leq 100\)).Each of the next \(n\) lines contains a binary string of... | For each test case print the integer \(k\) (\(0 \leq k \leq 3nm\)) β the number of operations.In the each of the next \(k\) lines print \(6\) integers \(x_1, y_1, x_2, y_2, x_3, y_3\) (\(1 \leq x_1, x_2, x_3 \leq n, 1 \leq y_1, y_2, y_3 \leq m\)) describing the next operation. This operation will be made with three cel... | In the first test case, it is possible to make only one operation with cells \((1, 1)\), \((2, 1)\), \((2, 2)\). After that, all symbols will be equal to \(0\).In the second test case: operation with cells \((2, 1)\), \((3, 1)\), \((3, 2)\). After it the table will be: 011001000 operation with cells \((1, 2)\), \((1, 3... | Input: 5 2 2 10 11 3 3 011 101 110 4 4 1111 0110 0110 1111 5 5 01011 11001 00010 11011 10000 2 3 011 101 | Output: 1 1 1 2 1 2 2 2 2 1 3 1 3 2 1 2 1 3 2 3 4 1 1 1 2 2 2 1 3 1 4 2 3 3 2 4 1 4 2 3 3 4 3 4 4 4 1 2 2 1 2 2 1 4 1 5 2 5 4 1 4 2 5 1 4 4 4 5 3 4 2 1 3 2 2 2 3 1 2 2 1 2 2 | Medium | 2 | 699 | 472 | 474 | 14 |
1,210 | E | 1210E | E. Wojtek and Card Tricks | 2,700 | math | Wojtek has just won a maths competition in Byteland! The prize is admirable β a great book called 'Card Tricks for Everyone.' 'Great!' he thought, 'I can finally use this old, dusted deck of cards that's always been lying unused on my desk!'The first chapter of the book is 'How to Shuffle \(k\) Cards in Any Order You W... | The first line contains two integers \(n\), \(k\) (\(1 \le n \le 200\,000\), \(1 \le k \le 5\)) β the number of tricks and the number of cards in Wojtek's deck.Each of the following \(n\) lines describes a single trick and is described by \(k\) distinct integers \(P_{i,1}, P_{i,2}, \dots, P_{i, k}\) (\(1 \le P_{i, j} \... | Output the value of the sum described in the statement. | Consider the first sample: The first trick swaps two top cards. The second trick takes a card from the bottom and puts it on the top of the deck. The third trick swaps two bottom cards. The first or the third trick allow Wojtek to generate only two distinct decks (either the two cards are swapped or not). Therefore, \(... | Input: 3 3 2 1 3 3 1 2 1 3 2 | Output: 25 | Master | 1 | 1,500 | 328 | 55 | 12 |
894 | C | 894C | C. Marco and GCD Sequence | 1,900 | constructive algorithms; math | In a dream Marco met an elderly man with a pair of black glasses. The man told him the key to immortality and then disappeared with the wind of time.When he woke up, he only remembered that the key was a sequence of positive integers of some length n, but forgot the exact sequence. Let the elements of the sequence be a... | The first line contains a single integer m (1 β€ m β€ 1000) β the size of the set S.The second line contains m integers s1, s2, ..., sm (1 β€ si β€ 106) β the elements of the set S. It's guaranteed that the elements of the set are given in strictly increasing order, that means s1 < s2 < ... < sm. | If there is no solution, print a single line containing -1.Otherwise, in the first line print a single integer n denoting the length of the sequence, n should not exceed 4000.In the second line print n integers a1, a2, ..., an (1 β€ ai β€ 106) β the sequence.We can show that if a solution exists, then there is a solution... | In the first example 2 = gcd(4, 6), the other elements from the set appear in the sequence, and we can show that there are no values different from 2, 4, 6 and 12 among gcd(ai, ai + 1, ..., aj) for every 1 β€ i β€ j β€ n. | Input: 42 4 6 12 | Output: 34 6 12 | Hard | 2 | 812 | 293 | 423 | 8 |
1,696 | A | 1696A | A. NIT orz! | 800 | bitmasks; greedy | NIT, the cleaver, is new in town! Thousands of people line up to orz him. To keep his orzers entertained, NIT decided to let them solve the following problem related to \(\operatorname{or} z\). Can you solve this problem too?You are given a 1-indexed array of \(n\) integers, \(a\), and an integer \(z\). You can do the ... | Each test contains multiple test cases. The first line contains the number of test cases \(t\) (\(1 \le t \le 100\)). Description of the test cases follows.The first line of each test case contains two integers \(n\) and \(z\) (\(1\le n\le 2000\), \(0\le z<2^{30}\)).The second line of each test case contains \(n\) inte... | For each test case, print one integer β the answer to the problem. | In the first test case of the sample, one optimal sequence of operations is: Do the operation with \(i=1\). Now \(a_1\) becomes \((3\operatorname{or}3)=3\) and \(z\) becomes \((3\operatorname{and}3)=3\). Do the operation with \(i=2\). Now \(a_2\) becomes \((4\operatorname{or}3)=7\) and \(z\) becomes \((4\operatorname{a... | Input: 52 33 45 50 2 4 6 81 9105 77 15 30 29 273 3954874310293834 10284344 13635445 | Output: 7 13 11 31 48234367 | Beginner | 2 | 949 | 466 | 66 | 16 |
1,525 | A | 1525A | A. Potion-making | 800 | math; number theory | You have an initially empty cauldron, and you want to brew a potion in it. The potion consists of two ingredients: magic essence and water. The potion you want to brew should contain exactly \(k\ \%\) magic essence and \((100 - k)\ \%\) water.In one step, you can pour either one liter of magic essence or one liter of w... | The first line contains the single \(t\) (\(1 \le t \le 100\)) β the number of test cases.The first and only line of each test case contains a single integer \(k\) (\(1 \le k \le 100\)) β the percentage of essence in a good potion. | For each test case, print the minimum number of steps to brew a good potion. It can be proved that it's always possible to achieve it in a finite number of steps. | In the first test case, you should pour \(3\) liters of magic essence and \(97\) liters of water into the cauldron to get a potion with \(3\ \%\) of magic essence.In the second test case, you can pour only \(1\) liter of essence to get a potion with \(100\ \%\) of magic essence.In the third test case, you can pour \(1\... | Input: 3 3 100 25 | Output: 100 1 4 | Beginner | 2 | 753 | 231 | 162 | 15 |
1,431 | D | 1431D | D. Used Markers | 1,500 | *special; greedy | Your University has a large auditorium and today you are on duty there. There will be \(n\) lectures today β all from different lecturers, and your current task is to choose in which order \(ord\) they will happen.Each lecturer will use one marker to write something on a board during their lecture. Unfortunately, marke... | The first line contains one integer \(t\) (\(1 \le t \le 100\)) β the number of independent tests.The first line of each test case contains one integer \(n\) (\(1 \le n \le 500\)) β the number of lectures and lecturers.The second line of each test case contains \(n\) integers \(a_1, a_2, \dots, a_n\) (\(1 \le a_i \le n... | For each test case, print \(n\) integers β the order \(ord\) of lecturers which maximizes the number of used markers. The lecturers are numbered from \(1\) to \(n\) in the order of the input. If there are multiple answers, print any of them. | In the first test case, one of the optimal orders is the following: the \(4\)-th lecturer comes first. The marker is new, so they don't ask for a replacement; the \(1\)-st lecturer comes next. The marker is used once and since \(a_1 = 1\) the lecturer asks for a replacement; the \(3\)-rd lecturer comes next. The second... | Input: 4 4 1 2 1 2 2 2 1 3 1 1 1 4 2 3 1 3 | Output: 4 1 3 2 1 2 3 1 2 4 3 2 1 | Medium | 2 | 1,642 | 361 | 241 | 14 |
1,791 | E | 1791E | E. Negatives and Positives | 1,100 | dp; greedy; sortings | Given an array \(a\) consisting of \(n\) elements, find the maximum possible sum the array can have after performing the following operation any number of times: Choose \(2\) adjacent elements and flip both of their signs. In other words choose an index \(i\) such that \(1 \leq i \leq n - 1\) and assign \(a_i = -a_i\) ... | The input consists of multiple test cases. The first line contains an integer \(t\) (\(1 \leq t \leq 1000\)) β the number of test cases. The descriptions of the test cases follow.The first line of each test case contains an integer \(n\) (\(2 \leq n \leq 2\cdot10^5\)) β the length of the array.The following line contai... | For each test case, output the maximum possible sum the array can have after performing the described operation any number of times. | For the first test case, by performing the operation on the first two elements, we can change the array from \([-1, -1, -1]\) to \([1, 1, -1]\), and it can be proven this array obtains the maximum possible sum which is \(1 + 1 + (-1) = 1\).For the second test case, by performing the operation on \(-5\) and \(0\), we ch... | Input: 53-1 -1 -151 5 -5 0 231 2 36-1 10 9 8 7 62-1 -1 | Output: 1 13 6 39 2 | Easy | 3 | 347 | 497 | 132 | 17 |
1,742 | B | 1742B | B. Increasing | 800 | greedy; implementation; sortings | You are given an array \(a\) of \(n\) positive integers. Determine if, by rearranging the elements, you can make the array strictly increasing. In other words, determine if it is possible to rearrange the elements such that \(a_1 < a_2 < \dots < a_n\) holds. | The first line contains a single integer \(t\) (\(1 \leq t \leq 100\)) β the number of test cases.The first line of each test case contains a single integer \(n\) (\(1 \leq n \leq 100\)) β the length of the array.The second line of each test case contains \(n\) integers \(a_i\) (\(1 \leq a_i \leq 10^9\)) β the elements... | For each test case, output ""YES"" (without quotes) if the array satisfies the condition, and ""NO"" (without quotes) otherwise.You can output the answer in any case (for example, the strings ""yEs"", ""yes"", ""Yes"" and ""YES"" will be recognized as a positive answer). | In the first test case any rearrangement will keep the array \([1,1,1,1]\), which is not strictly increasing.In the second test case, you can make the array \([1,3,4,7,8]\). | Input: 341 1 1 158 7 1 3 415 | Output: NO YES YES | Beginner | 3 | 258 | 334 | 271 | 17 |
773 | E | 773E | E. Blog Post Rating | 3,000 | data structures; sortings | It's well-known that blog posts are an important part of Codeforces platform. Every blog post has a global characteristic changing over time β its community rating. A newly created blog post's community rating is 0. Codeforces users may visit the blog post page and rate it, changing its community rating by +1 or -1.Con... | The first line contains a single integer n (1 β€ n β€ 5Β·105) β the number of Codeforces users.The second line contains n integers a1, a2, ..., an ( - 5Β·105 β€ ai β€ 5Β·105) β estimated blog post ratings for users in order from 1 to n. | For each k from 1 to n, output a single integer equal to the maximum possible community rating of the blog post after users with indices from 1 to k, in some order, visit the blog post page, rate the blog post, and close the page. | Input: 42 0 2 2 | Output: 1122 | Master | 2 | 1,556 | 229 | 230 | 7 | |
794 | C | 794C | C. Naming Company | 1,800 | games; greedy; sortings | Oleg the client and Igor the analyst are good friends. However, sometimes they argue over little things. Recently, they started a new company, but they are having trouble finding a name for the company.To settle this problem, they've decided to play a game. The company name will consist of n letters. Oleg and Igor each... | The first line of input contains a string s of length n (1 β€ n β€ 3Β·105). All characters of the string are lowercase English letters. This string denotes the set of letters Oleg has initially.The second line of input contains a string t of length n. All characters of the string are lowercase English letters. This string... | The output should contain a string of n lowercase English letters, denoting the company name if Oleg and Igor plays optimally. | One way to play optimally in the first sample is as follows : Initially, the company name is ???????. Oleg replaces the first question mark with 'f'. The company name becomes f??????. Igor replaces the second question mark with 'z'. The company name becomes fz?????. Oleg replaces the third question mark with 'f'. The c... | Input: tinkoffzscoder | Output: fzfsirk | Medium | 3 | 1,778 | 367 | 126 | 7 |
1,030 | B | 1030B | B. Vasya and Cornfield | 1,100 | geometry | Vasya owns a cornfield which can be defined with two integers \(n\) and \(d\). The cornfield can be represented as rectangle with vertices having Cartesian coordinates \((0, d), (d, 0), (n, n - d)\) and \((n - d, n)\). An example of a cornfield with \(n = 7\) and \(d = 2\). Vasya also knows that there are \(m\) grassho... | The first line contains two integers \(n\) and \(d\) (\(1 \le d < n \le 100\)).The second line contains a single integer \(m\) (\(1 \le m \le 100\)) β the number of grasshoppers.The \(i\)-th of the next \(m\) lines contains two integers \(x_i\) and \(y_i\) (\(0 \le x_i, y_i \le n\)) β position of the \(i\)-th grasshopp... | Print \(m\) lines. The \(i\)-th line should contain ""YES"" if the position of the \(i\)-th grasshopper lies inside or on the border of the cornfield. Otherwise the \(i\)-th line should contain ""NO"".You can print each letter in any case (upper or lower). | The cornfield from the first example is pictured above. Grasshoppers with indices \(1\) (coordinates \((2, 4)\)) and \(4\) (coordinates \((4, 5)\)) are inside the cornfield.The cornfield from the second example is pictured below. Grasshoppers with indices \(1\) (coordinates \((4, 4)\)), \(3\) (coordinates \((8, 1)\)) a... | Input: 7 242 44 16 34 5 | Output: YESNONOYES | Easy | 1 | 686 | 323 | 256 | 10 |
1,461 | C | 1461C | C. Random Events | 1,500 | dp; math; probabilities | Ron is a happy owner of a permutation \(a\) of length \(n\).A permutation of length \(n\) is an array consisting of \(n\) distinct integers from \(1\) to \(n\) in arbitrary order. For example, \([2,3,1,5,4]\) is a permutation, but \([1,2,2]\) is not a permutation (\(2\) appears twice in the array) and \([1,3,4]\) is al... | Each test contains one or more test cases. The first line contains the number of test cases \(t\) (\(1 \le t \le 100\)).The first line of each test case contains two integers \(n\) and \(m\) \((1 \le n, m \le 10^5)\) β the length of the permutation and the number of experiments, respectively.The second line of each tes... | For each test case, print a single number β the probability that after all experiments the permutation becomes sorted in ascending order. Your answer will be considered correct if its absolute or relative error does not exceed \(10^{-6}\).Formally, let your answer be \(a\), and the jury's answer be \(b\). Your answer i... | Explanation of the first test case: It can be demonstrated that whether the final permutation is sorted or not depends solely on sorting being performed in the \((4, 0.6)\) experiment. | Input: 4 4 3 4 3 2 1 1 0.3 3 1 4 0.6 5 3 4 2 1 3 5 3 0.8 4 0.6 5 0.3 6 5 1 3 2 4 5 6 4 0.9 5 0.3 2 0.4 6 0.7 3 0.5 4 2 1 2 3 4 2 0.5 4 0.1 | Output: 0.600000 0.720000 0.989500 1.000000 | Medium | 3 | 1,138 | 814 | 393 | 14 |
952 | C | 952C | C. Ravioli Sort | 1,600 | implementation | Everybody knows of spaghetti sort. You decided to implement an analog sorting algorithm yourself, but as you survey your pantry you realize you're out of spaghetti! The only type of pasta you have is ravioli, but you are not going to let this stop you...You come up with the following algorithm. For each number in the a... | The first line of input contains a single number n (1 β€ n β€ 10) β the size of the array.The second line of input contains n space-separated integers ai (1 β€ ai β€ 100) β the elements of the array. | Output ""YES"" if the array can be sorted using the described procedure and ""NO"" if it can not. | In the second example the array will change even before the tallest stack is chosen for the first time: ravioli from stack of height 3 will slide on the stack of height 1, and the algorithm will output an array {2, 2, 2}. | Input: 31 2 3 | Output: YES | Medium | 1 | 1,213 | 195 | 97 | 9 |
818 | C | 818C | C. Sofa Thief | 2,000 | brute force; implementation | Yet another round on DecoForces is coming! Grandpa Maks wanted to participate in it but someone has stolen his precious sofa! And how can one perform well with such a major loss?Fortunately, the thief had left a note for Grandpa Maks. This note got Maks to the sofa storehouse. Still he had no idea which sofa belongs to... | The first line contains one integer number d (1 β€ d β€ 105) β the number of sofas in the storehouse.The second line contains two integer numbers n, m (1 β€ n, m β€ 105) β the size of the storehouse.Next d lines contains four integer numbers x1, y1, x2, y2 (1 β€ x1, x2 β€ n, 1 β€ y1, y2 β€ m) β coordinates of the i-th sofa. It... | Print the number of the sofa for which all the conditions are met. Sofas are numbered 1 through d as given in input. If there is no such sofa then print -1. | Let's consider the second example. The first sofa has 0 to its left, 2 sofas to its right ((1, 1) is to the left of both (5, 5) and (5, 4)), 0 to its top and 2 to its bottom (both 2nd and 3rd sofas are below). The second sofa has cntl = 2, cntr = 1, cntt = 2 and cntb = 0. The third sofa has cntl = 2, cntr = 1, cntt = 1... | Input: 23 23 1 3 21 2 2 21 0 0 1 | Output: 1 | Hard | 2 | 1,400 | 555 | 156 | 8 |
1,002 | B4 | 1002B4 | B4. Distinguish four 2-qubit states - 2 | 1,700 | *special | You are given 2 qubits which are guaranteed to be in one of the four orthogonal states: Your task is to perform necessary operations and measurements to figure out which state it was and to return the index of that state (0 for , 1 for etc.). The state of the qubits after the operations does not matter.You have to impl... | Medium | 1 | 607 | 0 | 0 | 10 | ||||
1,131 | F | 1131F | F. Asya And Kittens | 1,700 | constructive algorithms; dsu | Asya loves animals very much. Recently, she purchased \(n\) kittens, enumerated them from \(1\) and \(n\) and then put them into the cage. The cage consists of one row of \(n\) cells, enumerated with integers from \(1\) to \(n\) from left to right. Adjacent cells had a partially transparent partition wall between them,... | The first line contains a single integer \(n\) (\(2 \le n \le 150\,000\)) β the number of kittens.Each of the following \(n - 1\) lines contains integers \(x_i\) and \(y_i\) (\(1 \le x_i, y_i \le n\), \(x_i \ne y_i\)) β indices of kittens, which got together due to the border removal on the corresponding day.It's guara... | For every cell from \(1\) to \(n\) print a single integer β the index of the kitten from \(1\) to \(n\), who was originally in it.All printed integers must be distinct.It's guaranteed, that there is at least one answer possible. In case there are multiple possible answers, print any of them. | The answer for the example contains one of several possible initial arrangements of the kittens.The picture below shows how the cells were united for this initial arrangement. Note, that the kittens who wanted to play together on each day were indeed in adjacent cells. | Input: 5 1 4 2 5 3 1 4 5 | Output: 3 1 4 2 5 | Medium | 2 | 1,295 | 408 | 292 | 11 |
1,409 | A | 1409A | A. Yet Another Two Integers Problem | 800 | greedy; math | You are given two integers \(a\) and \(b\).In one move, you can choose some integer \(k\) from \(1\) to \(10\) and add it to \(a\) or subtract it from \(a\). In other words, you choose an integer \(k \in [1; 10]\) and perform \(a := a + k\) or \(a := a - k\). You may use different values of \(k\) in different moves.You... | The first line of the input contains one integer \(t\) (\(1 \le t \le 2 \cdot 10^4\)) β the number of test cases. Then \(t\) test cases follow.The only line of the test case contains two integers \(a\) and \(b\) (\(1 \le a, b \le 10^9\)). | For each test case, print the answer: the minimum number of moves required to obtain \(b\) from \(a\). | In the first test case of the example, you don't need to do anything.In the second test case of the example, the following sequence of moves can be applied: \(13 \rightarrow 23 \rightarrow 32 \rightarrow 42\) (add \(10\), add \(9\), add \(10\)).In the third test case of the example, the following sequence of moves can ... | Input: 6 5 5 13 42 18 4 1337 420 123456789 1000000000 100500 9000 | Output: 0 3 2 92 87654322 9150 | Beginner | 2 | 450 | 238 | 102 | 14 |
447 | B | 447B | B. DZY Loves Strings | 1,000 | greedy; implementation | DZY loves collecting special strings which only contain lowercase letters. For each lowercase letter c DZY knows its value wc. For each special string s = s1s2... s|s| (|s| is the length of the string) he represents its value with a function f(s), where Now DZY has a string s. He wants to insert k lowercase letters int... | The first line contains a single string s (1 β€ |s| β€ 103).The second line contains a single integer k (0 β€ k β€ 103).The third line contains twenty-six integers from wa to wz. Each such number is non-negative and doesn't exceed 1000. | Print a single integer β the largest possible value of the resulting string DZY could get. | In the test sample DZY can obtain ""abcbbc"", value = 1Β·1 + 2Β·2 + 3Β·2 + 4Β·2 + 5Β·2 + 6Β·2 = 41. | Input: abc31 2 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 | Output: 41 | Beginner | 2 | 469 | 232 | 90 | 4 |
225 | C | 225C | C. Barcode | 1,700 | dp; matrices | You've got an n Γ m pixel picture. Each pixel can be white or black. Your task is to change the colors of as few pixels as possible to obtain a barcode picture.A picture is a barcode if the following conditions are fulfilled: All pixels in each column are of the same color. The width of each monochrome vertical line is... | The first line contains four space-separated integers n, m, x and y (1 β€ n, m, x, y β€ 1000; x β€ y).Then follow n lines, describing the original image. Each of these lines contains exactly m characters. Character ""."" represents a white pixel and ""#"" represents a black pixel. The picture description doesn't have any ... | In the first line print the minimum number of pixels to repaint. It is guaranteed that the answer exists. | In the first test sample the picture after changing some colors can looks as follows: .##...##...##...##...##...##.. In the second test sample the picture after changing some colors can looks as follows: .#.#..#.#. | Input: 6 5 1 2##.#..###.###..#...#.##.####.. | Output: 11 | Medium | 2 | 503 | 361 | 105 | 2 |
730 | C | 730C | C. Bulmart | 2,100 | binary search; dfs and similar | A new trade empire is rising in Berland. Bulmart, an emerging trade giant, decided to dominate the market of ... shovels! And now almost every city in Berland has a Bulmart store, and some cities even have several of them! The only problem is, at the moment sales are ... let's say a little below estimates. Some people ... | The first line contains two integers n, m (1 β€ n β€ 5000, 0 β€ m β€ min(5000, nΒ·(n - 1) / 2)). Each of the next m lines contains two integers xe and ye, meaning that the e-th road connects cities xe and ye (1 β€ xe, ye β€ n).The next line contains a single integer w (1 β€ w β€ 5000) β the total number of Bulmart stores in Ber... | Output q lines. On the j-th line, print an answer for the j-th query β the minimum amount of time needed to deliver rj shovels to the customer in city gj spending no more than aj burles. Print -1 if there is no solution for the j-th query. | Input: 6 44 25 41 23 224 1 23 2 361 2 62 3 73 1 24 3 85 2 56 1 10 | Output: 2-1223-1 | Hard | 2 | 1,836 | 648 | 239 | 7 | |
567 | F | 567F | F. Mausoleum | 2,400 | dp | King of Berland Berl IV has recently died. Hail Berl V! As a sign of the highest achievements of the deceased king the new king decided to build a mausoleum with Berl IV's body on the main square of the capital.The mausoleum will be constructed from 2n blocks, each of them has the shape of a cuboid. Each block has the ... | The first line of the input contains integers n and k (1 β€ n β€ 35, 0 β€ k β€ 100) β the number of pairs of blocks and the number of additional requirements.Next k lines contain listed additional requirements, one per line in the format ""xi signi yi"" (1 β€ xi, yi β€ 2n), and the sign is on of the list of the five possible... | Print the sought number of ways. | Input: 3 0 | Output: 9 | Expert | 1 | 1,755 | 327 | 32 | 5 | |
218 | A | 218A | A. Mountain Scenery | 1,100 | brute force; constructive algorithms; implementation | Little Bolek has found a picture with n mountain peaks painted on it. The n painted peaks are represented by a non-closed polyline, consisting of 2n segments. The segments go through 2n + 1 points with coordinates (1, y1), (2, y2), ..., (2n + 1, y2n + 1), with the i-th segment connecting the point (i, yi) and the point... | The first line contains two space-separated integers n and k (1 β€ k β€ n β€ 100). The next line contains 2n + 1 space-separated integers r1, r2, ..., r2n + 1 (0 β€ ri β€ 100) β the y coordinates of the polyline vertices on Bolek's picture.It is guaranteed that we can obtain the given picture after performing the described ... | Print 2n + 1 integers y1, y2, ..., y2n + 1 β the y coordinates of the vertices of the polyline on the initial picture. If there are multiple answers, output any one of them. | Input: 3 20 5 3 5 1 5 2 | Output: 0 5 3 4 1 4 2 | Easy | 3 | 1,171 | 362 | 173 | 2 | |
618 | D | 618D | D. Hamiltonian Spanning Tree | 2,200 | dfs and similar; dp; graph matchings; greedy; trees | A group of n cities is connected by a network of roads. There is an undirected road between every pair of cities, so there are roads in total. It takes exactly y seconds to traverse any single road.A spanning tree is a set of roads containing exactly n - 1 roads such that it's possible to travel between any two cities ... | The first line of the input contains three integers n, x and y (2 β€ n β€ 200 000, 1 β€ x, y β€ 109).Each of the next n - 1 lines contains a description of a road in the spanning tree. The i-th of these lines contains two integers ui and vi (1 β€ ui, vi β€ n) β indices of the cities connected by the i-th road. It is guarante... | Print a single integer β the minimum number of seconds one needs to spend in order to visit all the cities exactly once. | In the first sample, roads of the spanning tree have cost 2, while other roads have cost 3. One example of an optimal path is .In the second sample, we have the same spanning tree, but roads in the spanning tree cost 3, while other roads cost 2. One example of an optimal path is . | Input: 5 2 31 21 33 45 3 | Output: 9 | Hard | 5 | 818 | 361 | 120 | 6 |
215 | B | 215B | B. Olympic Medal | 1,300 | greedy; math | The World Programming Olympics Medal is a metal disk, consisting of two parts: the first part is a ring with outer radius of r1 cm, inner radius of r2 cm, (0 < r2 < r1) made of metal with density p1 g/cm3. The second part is an inner disk with radius r2 cm, it is made of metal with density p2 g/cm3. The disk is nested ... | The first input line contains an integer n and a sequence of integers x1, x2, ..., xn. The second input line contains an integer m and a sequence of integers y1, y2, ..., ym. The third input line contains an integer k and a sequence of integers z1, z2, ..., zk. The last line contains two integers A and B.All numbers gi... | Print a single real number β the sought value r2 with absolute or relative error of at most 10 - 6. It is guaranteed that the solution that meets the problem requirements exists. | In the first sample the jury should choose the following values: r1 = 3, p1 = 2, p2 = 1. | Input: 3 1 2 31 23 3 2 11 2 | Output: 2.683281573000 | Easy | 2 | 1,196 | 478 | 178 | 2 |
1,753 | F | 1753F | F. Minecraft Series | 3,500 | brute force; two pointers | Little Misha goes to the programming club and solves nothing there. It may seem strange, but when you find out that Misha is filming a Minecraft series, everything will fall into place...Misha is inspired by Manhattan, so he built a city in Minecraft that can be imagined as a table of size \(n \times m\). \(k\) student... | The first line contains four integers \(n\), \(m\), \(k\) and \(t\) (\(1 \le n, m \le 40\,000\), \(1 \le n \cdot m \le 40\,000\), \(1 \le k \le 10^6\), \(1 \le t \le k + 1\)) β the number of rows and columns in the table, and the number of students living in the city, respectively.Each of the following \(k\) lines cont... | Print one integer β the number of ways to choose the square \(s\) in such way that the main hero will be able to form a team of at least \(t\) people. | In the first example the main hero will not be able to form a team of more than one person in any square \(s\). Illustration for the first example. In the second example there are two ways to select square \(s\). Both of them are illustrated below. In one of them the main hero will be able to form a team of students wi... | Input: 2 2 1 2 1 1 2 | Output: 0 | Master | 2 | 1,842 | 557 | 150 | 17 |
131 | C | 131C | C. The World is a Theatre | 1,400 | combinatorics; math | There are n boys and m girls attending a theatre club. To set a play ""The Big Bang Theory"", they need to choose a group containing exactly t actors containing no less than 4 boys and no less than one girl. How many ways are there to choose a group? Of course, the variants that only differ in the composition of the tr... | The only line of the input data contains three integers n, m, t (4 β€ n β€ 30, 1 β€ m β€ 30, 5 β€ t β€ n + m). | Find the required number of ways.Please do not use the %lld specificator to read or write 64-bit integers in Π‘++. It is preferred to use cin, cout streams or the %I64d specificator. | Input: 5 2 5 | Output: 10 | Easy | 2 | 451 | 104 | 181 | 1 | |
62 | A | 62A | A. A Student's Dream | 1,300 | greedy; math | Statistics claims that students sleep no more than three hours a day. But even in the world of their dreams, while they are snoring peacefully, the sense of impending doom is still upon them.A poor student is dreaming that he is sitting the mathematical analysis exam. And he is examined by the most formidable professor... | The first line contains two positive integers not exceeding 100. They are the number of fingers on the Venusian girl's left and right hand correspondingly. The second line contains two integers not exceeding 100. They are the number of fingers on the Marsian boy's left and right hands correspondingly. | Print YES or NO, that is, the answer to Petr Palych's question. | The boy and the girl don't really care who goes to the left. | Input: 5 110 5 | Output: YES | Easy | 2 | 1,553 | 302 | 63 | 0 |
802 | M | 802M | M. April Fools' Problem (easy) | 1,200 | greedy; sortings | The marmots have prepared a very easy problem for this year's HC2 β this one. It involves numbers n, k and a sequence of n positive integers a1, a2, ..., an. They also came up with a beautiful and riveting story for the problem statement. It explains what the input means, what the program should output, and it also rea... | The first line of the input contains two space-separated integers n and k (1 β€ k β€ n β€ 2200). The second line contains n space-separated integers a1, ..., an (1 β€ ai β€ 104). | Output one number. | Input: 8 51 1 1 1 1 1 1 1 | Output: 5 | Easy | 2 | 534 | 173 | 18 | 8 | |
2,122 | E | 2122E | E. Greedy Grid Counting | 2,600 | combinatorics; dp; greedy; math | A path in a grid is called greedy if it starts at the top-left cell and moves only to the right or downward, always moving to its neighbor with the greater value (or either if the values are equal).The value of a path is the sum of the values of the cells it visits, including the start and end.Given a partially filled ... | Each test contains multiple test cases. The first line contains the number of test cases \(t\) (\(1 \le t \le 500\)). The description of the test cases follows. The first line of each test case contains two integers \(n\) and \(k\) (\(1 \leq n, k \leq 500\)) β the number of columns and the range of integers in the grid... | For each test case, output a single integer β the number of ways to fill the grid that satisfy the above conditions, modulo \(998\,244\,353\). | In the first test case, the grids that satisfy the conditions are: $$$\( \begin{bmatrix} 2 & 1 & 1 & 2 \\ 2 & 1 & 1 & 3 \end{bmatrix},\: \begin{bmatrix} 2 & 1 & 1 & 2 \\ 2 & 2 & 1 & 3 \end{bmatrix},\: \begin{bmatrix} 2 & 1 & 1 & 2 \\ 2 & 3 & 1 & 3 \end{bmatrix},\: \begin{bmatrix} 2 & 1 & 2 & 2 \\ 2 & 2 & 1 & 3 \end{bma... | Input: 34 32 1 -1 22 -1 1 35 41 3 -1 4 2-1 3 4 2 -110 10-1 -1 -1 -1 -1 -1 -1 -1 -1 -1-1 -1 -1 -1 -1 -1 -1 -1 -1 -1 | Output: 6 64 123782927 | Expert | 4 | 864 | 665 | 142 | 21 |
550 | D | 550D | D. Regular Bridge | 1,900 | constructive algorithms; graphs; implementation | An undirected graph is called k-regular, if the degrees of all its vertices are equal k. An edge of a connected graph is called a bridge, if after removing it the graph is being split into two connected components.Build a connected undirected k-regular graph containing at least one bridge, or else state that such graph... | The single line of the input contains integer k (1 β€ k β€ 100) β the required degree of the vertices of the regular graph. | Print ""NO"" (without quotes), if such graph doesn't exist. Otherwise, print ""YES"" in the first line and the description of any suitable graph in the next lines.The description of the made graph must start with numbers n and m β the number of vertices and edges respectively. Each of the next m lines must contain two ... | In the sample from the statement there is a suitable graph consisting of two vertices, connected by a single edge. | Input: 1 | Output: YES2 11 2 | Hard | 3 | 335 | 121 | 979 | 5 |
1,927 | A | 1927A | A. Make it White | 800 | greedy; strings | You have a horizontal strip of \(n\) cells. Each cell is either white or black.You can choose a continuous segment of cells once and paint them all white. After this action, all the black cells in this segment will become white, and the white ones will remain white.What is the minimum length of the segment that needs t... | The first line of the input contains a single integer \(t\) (\(1 \le t \le 10^4\)) β the number of test cases. The descriptions of the test cases follow.The first line of each test case contains a single integer \(n\) (\(1 \le n \le 10\)) β the length of the strip.The second line of each test case contains a string \(s... | For each test case, output a single number β the minimum length of a continuous segment of cells that needs to be painted white in order for the entire strip to become white. | In the first test case of the example for the strip ""WBBWBW"", the minimum length of the segment to be repainted white is \(4\). It is necessary to repaint to white the segment from the \(2\)-nd to the \(5\)-th cell (the cells are numbered from \(1\) from left to right). | Input: 86WBBWBW1B2WB3BBW4BWWB6BWBWWB6WWBBWB9WBWBWWWBW | Output: 4 1 1 2 4 6 4 7 | Beginner | 2 | 384 | 520 | 174 | 19 |
986 | E | 986E | E. Prince's Problem | 2,800 | brute force; data structures; math; number theory; trees | Let the main characters of this problem be personages from some recent movie. New Avengers seem to make a lot of buzz. I didn't watch any part of the franchise and don't know its heroes well, but it won't stop me from using them in this problem statement. So, Thanos and Dr. Strange are doing their superhero and supervi... | In the first line of input there is one integer \(n\) (\(1 \le n \le 10^{5}\)) β the size of the tree.In the next \(n-1\) lines the edges of the tree are described. The \(i\)-th edge is described with two integers \(u_{i}\) and \(v_{i}\) (\(1 \le u_{i}, v_{i} \le n\)) and it connects the vertices \(u_{i}\) and \(v_{i}\... | Print \(q\) numbers β the answers to the queries in the order they are given in the input. Print each answer modulo \(10^9+7 = 1000000007\). Print each number on a separate line. | Input: 41 21 31 46 4 9 532 3 62 3 23 4 7 | Output: 3641 | Master | 5 | 1,213 | 761 | 178 | 9 |
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